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Sample records for live vaccine strain

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

    DTIC Science & Technology

    2006-03-31

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

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

    PubMed

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

    2014-07-01

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

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

    PubMed

    Ferguson-Noel, N M; Williams, S M

    2015-01-01

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

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

    PubMed

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

    2016-11-01

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

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

    PubMed

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

    2013-10-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    DTIC Science & Technology

    1983-05-20

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed

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

    2008-12-01

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

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

    PubMed

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

    2009-07-16

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

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

    PubMed

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

    2015-07-01

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

  12. Identification of in vitro upregulated genes in a modified live vaccine strain of Edwardsiella ictaluri compared to a virulent parent strain

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. Comparison of the Live Attenuated Yellow Fever Vaccine 17D-204 Strain to Its Virulent Parental Strain Asibi by Deep Sequencing

    PubMed Central

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

    2014-01-01

    Background. The first comparison of a live RNA viral vaccine strain to its wild-type parental strain by deep sequencing is presented using as a model the yellow fever virus (YFV) live vaccine strain 17D-204 and its wild-type parental strain, Asibi. Methods. The YFV 17D-204 vaccine genome was compared to that of the parental strain Asibi by massively parallel methods. Variability was compared on multiple scales of the viral genomes. A modeled exploration of small-frequency variants was performed to reconstruct plausible regions of mutational plasticity. Results. Overt quasispecies diversity is a feature of the parental strain, whereas the live vaccine strain lacks diversity according to multiple independent measurements. A lack of attenuating mutations in the Asibi population relative to that of 17D-204 was observed, demonstrating that the vaccine strain was derived by discrete mutation of Asibi and not by selection of genomes in the wild-type population. Conclusions. Relative quasispecies structure is a plausible correlate of attenuation for live viral vaccines. Analyses such as these of attenuated viruses improve our understanding of the molecular basis of vaccine attenuation and provide critical information on the stability of live vaccines and the risk of reversion to virulence. PMID:24141982

  14. Differentiation of Erysipelothrix rhusiopathiae strains by nucleotide sequence analysis of a hypervariable region in the spaA gene: discrimination of a live vaccine strain from field isolates.

    PubMed

    Nagai, Shinya; To, Ho; Kanda, Akira

    2008-05-01

    Erysipelothrix rhusiopathiae causes erysipelas in swine and is considered a reemerging disease contributing substantially to economic losses in the swine industry. Since an attenuated live vaccine was commercialized in 1974 in Japan, outbreaks of acute septicemia or subacute urticaria of erysipelas have decreased dramatically. In contrast, a chronic form of erysipelas found during meat inspections in slaughterhouses has been increasing. In this study, a new strain-typing method was developed based on nucleotide sequencing of a hypervariable region in the surface protective antigen (spaA) gene for discrimination of the live vaccine strain from field isolates. Sixteen strains isolated from arthritic lesions found in slaughtered pigs were segregated into 4 major patterns: 1) identical nucleotide sequence with the vaccine strain: 3 isolates; 2) 1 nucleotide substitution (C to A) at position 555: 5 isolates; 3) 1 nucleotide substitution at various positions: 5 isolates; and 4) 2 nucleotide substitutions: 3 isolates. Isolates with the same nucleotide sequence as the vaccine strain were further characterized by other properties, including the mouse pathogenicity test. One strain isolated from pigs on a farm where the live vaccine had been used was found to be closely related to the vaccine strain. The phylogenetic tree constructed based on the spaA sequence suggests that the evolutionary distance of the isolates is related to the pathogenicity in mice. The new strain-typing system based on nucleotide sequencing of the spaA region is useful to discriminate the vaccine strain from field isolates.

  15. Experimental study of a further attenuated live measles vaccine of the Sugiyama strain in Iran

    PubMed Central

    Mirchamsy, H.; Shafyi, A.; Rafyi, M. R.; Bahrami, S.; Nazari, P.; Fatemie, S.

    1974-01-01

    After encouraging results of the mass vaccination programme in Iran, in which 5 million children in rural areas were vaccinated with the Japanese Sugiyama strain at its 82nd passage in baby calf kidney, and a progressive decrease in the incidence of measles as well as a reduction of excessive infant mortality, a further attenuated vaccine, produced with the same strain, cloned in Japan, was compared in a field trial with the parent vaccine. The new strain caused fewer reactions than the original strain. Seroconversion with a geometric mean antibody titre of 6·1 was observed in 95% of susceptible children. PMID:4522721

  16. A reassortment-incompetent live attenuated influenza virus vaccine for use in protection against pandemic virus strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although live-attenuated influenza vaccines (LAIV) are safe for use in protection against seasonal influenza strains, concerns over their potential to reassort with wild-type virus strains have been voiced. LAIVs have been demonstrated to induce enhanced mucosal and cell-mediated immunity over inac...

  17. Influenza Vaccine, Live Intranasal

    MedlinePlus

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

  18. African horse sickness in The Gambia: circulation of a live-attenuated vaccine-derived strain.

    PubMed

    Oura, C A L; Ivens, P A S; Bachanek-Bankowska, K; Bin-Tarif, A; Jallow, D B; Sailleau, C; Maan, S; Mertens, P C; Batten, C A

    2012-03-01

    African horse sickness virus serotype 9 (AHSV-9) has been known for some time to be circulating amongst equids in West Africa without causing any clinical disease in indigenous horse populations. Whether this is due to local breeds of horses being resistant to disease or whether the AHSV-9 strains circulating are avirulent is currently unknown. This study shows that the majority (96%) of horses and donkeys sampled across The Gambia were seropositive for AHS, despite most being unvaccinated and having no previous history of showing clinical signs of AHS. Most young horses (<3 years) were seropositive with neutralizing antibodies specific to AHSV-9. Eight young equids (<3 years) were positive for AHSV-9 by serotype-specific RT-PCR and live AHSV-9 was isolated from two of these horses. Sequence analysis revealed the presence of an AHSV-9 strain showing 100% identity to Seg-2 of the AHSV-9 reference strain, indicating that the virus circulating in The Gambia was highly likely to have been derived from a live-attenuated AHSV-9 vaccine strain.

  19. Clinical trials with Alice strain, live, attenuated, serum inhibitor-resistant intranasal influenza A vaccine.

    PubMed

    Spencer, M J; Cherry, J D; Powell, K R; Sumaya, C V; Garakian, A J

    1975-10-01

    Two clinical trials with Alice strain intranasal influenza vaccine were performed. In study no. 1 (utilizing random selection and double-blind control), 50 subjects received a bivalent inactivated influenza vaccine intramuscularly, 99 subjects received Alice strain vaccine intranasally, and 50 subjects received a placebo intranasally. No symptomatology could be attributed to the intranasal route of immunization. Convalescent-phase geometric mean titers of hemagglutination inhibition antibody were higher after intramuscular vaccination; seroconversion occurred in 16 or 17 recipients of the Alice strain, with initial titers of less than 1:8. Clinical and virologic surveillance for 20 weeks after vaccination revealed no influenza A illnesses in participants of the study. In study no. 2, 75% of the subjects with initial nasal antibody titers of less than 1:3 developed measurable nasal antibody after receiving Alice strain vaccine.

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

    PubMed

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

    2010-12-10

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

  1. Generation of a live rabies vaccine strain attenuated by multiple mutations and evaluation of its safety and efficacy.

    PubMed

    Nakagawa, Keisuke; Ito, Naoto; Masatani, Tatsunori; Abe, Masako; Yamaoka, Satoko; Ito, Yuki; Okadera, Kota; Sugiyama, Makoto

    2012-05-21

    An amino acid substitution at position 333 in rabies virus G protein is known to determine the pathogenicity: strains with Arg or Lys at that position kill adult mice after intracerebral inoculation, whereas strains with other amino acids cause non-lethal infection. Based on those findings, attenuated rabies virus strains have been established and used for oral vaccines mainly for wild animals. However, considering the possibility of back-mutation to the virulent phenotype, a strain that is attenuated by multiple mutations not only in the G protein but also in other viral proteins would be more appropriate as a safe live vaccine. We previously demonstrated that the fixed rabies virus Ni-CE strain, which causes only transient body weight loss in adult mice after intracerebral inoculation, is mainly attenuated by mutations in the N, P and M proteins, while this strain has virulent-type Arg at position 333 in the G protein. In this study, to obtain a live vaccine strain that is attenuated by multiple mutations, we generated Ni-CE mutant, Ni-CE(G333Glu) strain, which has an Arg-to-Glu mutation at position 333 in the G protein, and examined its pathogenicity and immunogenicity. We found that, in contrast to Ni-CE strain, Ni-CE(G333Glu) strain did not cause transient body weight loss in adult mice after intracerebral inoculation. The attenuated phenotype of Ni-CE(G333Glu) strain did not change even after 10 serial intracerebral passages in suckling mice. We also demonstrated that inoculation of Ni-CE(G333Glu) strain induced virus-neutralizing antibody in immunized mice and protected the mice from lethal challenge. These results indicate that Ni-CE(G333Glu) strain is a promising candidate for development of a live rabies vaccine with a high safety level.

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

    PubMed

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

    2012-09-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed

    Lashkevich, V A

    2013-01-01

    In 1958 Poliomyelitis Institute in Moscow and Institute of Experimental Medicine in St. Petersburg received from A. Sabin the attenuated strains of poliomyelitis virus. The characteristics of the strains were thoroughly studied by A. A. Smorodintsev and coworkers. They found that the virulence of the strains fluctuated slightly in 10 consecutive passages through the intestine of the non-immune children. A part of the Sabin material was used by A. A. Smorodintsev and M. P. Chumakov in the beginning of 1959 for immunizing approximately 40000 children in Estonia, Lithuania, and Latvia. Epidemic poliomyelitis rate in these republics decreased from approximately 1000 cases yearly before vaccination to less than 20 in the third quarter of 1959. This was a convincing proof of the efficacy and safety of the vaccine from the attenuated Sabin strains. In 1959, according to A. Sabin's recommendation, a technology of live vaccine production was developed at the Poliomyelitis Institute, and several experimental lots of vaccine were prepared. In the second part of 1959, 13.5 million children in USSR were immunized. The epidemic poliomyelitis rate decreased 3-5 times in different regions without paralytic cases, which could be attributed to the vaccination. These results were the final proof of high efficiency and safety of live poliomyelitis vaccine from the attenuated Sabin strains. Based on these results, A. Sabin and M. P. Chumakov suggested in 1960 the idea of poliomyelitis eradication using mass immunization of children with live vaccine. 72 million persons up to 20 years old were vaccinated in USSR in 1960 with a 5 times drop in the paralytic rate. 50-year-long use of live vaccine results in poliomyelitis eradication in almost all countries worldwide. More than 10 million children were rescued from the death and palsy. Poliomyelitis eradication in a few countries where it still exists depends not on medical services but is defined by the attitude of their leaders to fight

  5. GroEL and Lipopolysaccharide from Francisella tularensis Live Vaccine Strain Synergistically Activate Human Macrophages ▿

    PubMed Central

    Noah, Courtney E.; Malik, Meenakshi; Bublitz, DeAnna C.; Camenares, Devin; Sellati, Timothy J.; Benach, Jorge L.; Furie, Martha B.

    2010-01-01

    Francisella tularensis, the causative agent of tularemia, interacts with host cells of innate immunity in an atypical manner. For most Gram-negative bacteria, the release of lipopolysaccharide (LPS) from their outer membranes stimulates an inflammatory response. When LPS from the attenuated live vaccine strain (LVS) or the highly virulent Schu S4 strain of F. tularensis was incubated with human umbilical vein endothelial cells, neither species of LPS induced expression of the adhesion molecule E-selectin or secretion of the chemokine CCL2. Moreover, a high concentration (10 μg/ml) of LVS or Schu S4 LPS was required to stimulate production of CCL2 by human monocyte-derived macrophages (huMDM). A screen for alternative proinflammatory factors of F. tularensis LVS identified the heat shock protein GroEL as a potential candidate. Recombinant LVS GroEL at a concentration of 10 μg/ml elicited secretion of CXCL8 and CCL2 by huMDM through a TLR4-dependent mechanism. When 1 μg of LVS GroEL/ml was added to an equivalent amount of LVS LPS, the two components synergistically activated the huMDM to produce CXCL8. Schu S4 GroEL was less stimulatory than LVS GroEL and showed a lesser degree of synergy when combined with Schu S4 LPS. These findings suggest that the intrinsically low proinflammatory activity of F. tularensis LPS may be increased in the infected human host through interactions with other components of the bacterium. PMID:20123721

  6. Control of Salmonella Enteritidis and Salmonella Gallinarum in birds by using live vaccine candidate containing attenuated Salmonella Gallinarum mutant strain.

    PubMed

    Penha Filho, Rafael Antonio Casarin; de Paiva, Jacqueline Boldrin; da Silva, Mariana Dias; de Almeida, Adriana Maria; Berchieri, Angelo

    2010-04-01

    The ideal live vaccine to control Salmonella in commercial chicken flocks should engender protection against various strains. The purpose of the present study was to confirm the attenuation of a Salmonella Gallinarum (SG) mutant strain with deletion on genes cobS and cbiA, that are involved in the biosynthesis of cobalamin. Furthermore, evaluate its use as a live vaccine against Salmonella. For the evaluation of the vaccine efficacy, two experiments were conducted separately. Birds from a commercial brown line of chickens were used to perform challenge with SG wild type strain and birds from a commercial white line of chickens were used to perform challenge with Salmonella Enteritidis (SE) wild type strain. In both experiments, the birds were separated in three groups (A, B and C). Birds were orally vaccinated with the SG mutant as the following programme: group A, one dose at 5 days of age; group B, one dose at 5 days of age and a second dose at 25 days of age; and group C, birds were kept unvaccinated as controls. At 45 days of age, birds from all groups, including the control, were challenged orally by SG wild type (brown line) or SE wild type (white line). Lastly, another experiment was performed to evaluate the use of the SG mutant strain to prevent caecal colonization by SE wild type on 1-day-old broiler chicks. Mortality and systemic infection by SG wild type strain were assessed in brown chickens; faecal shedding and systemic infection by SE wild type were assessed in white chickens and caecal colonization was assessed in broiler chicks. Either vaccination with one or two doses of SG mutant, were capable to protect brown chickens against SG wild type. In the experiment with white chickens, only vaccination with two doses of SG mutant protected the birds against challenge with SE wild type. Although, SG mutant could not prevent caecal colonization in 1-day-old broiler chicks by the challenge strain SE wild type. Overall, the results indicated that SG mutant

  7. Live Virus Smallpox Vaccine

    MedlinePlus

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

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

    PubMed Central

    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

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

    PubMed Central

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

    2000-01-01

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

  10. Aged mice display an altered pulmonary host response to Francisella tularensis live vaccine strain (LVS) infections

    PubMed Central

    CA, Mares; SS, Ojeda; Q, Li; EG, Morris; JJ, Coalson; JM, Teale

    2012-01-01

    Aging is a complex phenomenon that has been shown to affect many organ systems including the innate and adaptive immune systems. The current study was designed to examine the potential effect of immunosenescence on the pulmonary immune response using a Francisella tularensis live vaccine strain (LVS) inhalation infection model. F. tularensis is a gram-negative intracellular pathogen that can cause a severe pneumonia.In this study both young (8-12 week old) and aged (20-24 month old) mice were infected intranasally with LVS. Lung tissues from young and aged mice were used to assess pathology, recruitment of immune cell types and cytokine expression levels at various times post infection. Bacterial burdens were also assessed. Interestingly, the lungs of aged animals harbored fewer organisms at early time points of infection (day 1, day 3) compared with their younger counterparts. In addition, only aged animals displayed small perivascular aggregates at these early time points that appeared mostly mononuclear in nature. However, the kinetics of infiltrating polymorphonuclear neutrophils (PMNs) and increased cytokine levels measured in the bronchial alveolar lavage fluid (BALF) were delayed in infected aged animals relative to young infected animals with neutrophils appearing at day 5 post infection (PI) in the aged animals as opposed to day 3 PI in the young infected animals. Also evident were alterations in the ratios of mononuclear to PMNs at distinct post infection times. The above evidence indicates that aged mice elicit an altered immune response in the lung to respiratory Francisella tularensis LVS infections compared to their younger counterparts. PMID:19825409

  11. Biology of Francisella tularensis Subspecies holarctica Live Vaccine Strain in the Tick Vector Dermacentor variabilis

    PubMed Central

    Mani, Rinosh J.; Reichard, Mason V.; Morton, Rebecca J.; Kocan, Katherine M.; Clinkenbeard, Kenneth D.

    2012-01-01

    Background The γ-proteobacterium Francisella tularensis is the etiologic agent of seasonal tick-transmitted tularemia epizootics in rodents and rabbits and of incidental infections in humans. The biology of F. tularensis in its tick vectors has not been fully described, particularly with respect to its quanta and duration of colonization, tissue dissemination, and transovarial transmission. A systematic study of the colonization of Dermacentor variabilis by the F. tularensis subsp. holarctica live vaccine strain (LVS) was undertaken to better understand whether D. variabilis may serve as an inter-epizootic reservoir for F. tularensis. Methodology/Principal Findings Colony-reared larva, nymph, and adult D. variabilis were artificially fed LVS via glass capillary tubes fitted over the tick mouthparts, and the level of colonization determined by microbial culture. Larvae and nymphs were initially colonized with 8.8±0.8×101 and 1.1±0.03×103 CFU/tick, respectively. Post-molting, a significant increase in colonization of both molted nymphs and adults occurred, and LVS persisted in 42% of molted adult ticks at 126 days post-capillary tube feeding. In adult ticks, LVS initially colonized the gut, disseminated to hemolymph and salivary glands by 21 days, and persisted up to 165 days. LVS was detected in the salivary secretions of adult ticks after four days post intra-hemocoelic inoculation, and LVS recovered from salivary gland was infectious to mice with an infectious dose 50% of 3 CFU. LVS in gravid female ticks colonized via the intra-hemocoelic route disseminated to the ovaries and then to the oocytes, but the pathogen was not recovered from the subsequently-hatched larvae. Conclusions/Significance This study demonstrates that D. variabilis can be efficiently colonized with F. tularensis using artificial methods. The persistence of F. tularensis in D. variabilis suggests that this tick species may be involved in the maintenance of enzootic foci of tularemia in the

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

    PubMed Central

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

    2016-01-01

    Vaccination is a useful option to control infection with porcine reproductive and respiratory syndrome virus (PRRSV), and several modified live-PRRSV vaccines have been developed. These vaccines have shown some efficacy in reducing the incidence and severity of clinical disease as well as the duration of viremia and virus shedding but have failed to provide sterilizing immunity. The efficacy of modified live-virus (MLV) vaccines is greater against a homologous strain compared with heterologous PRRSV strains. The objective of this study was to evaluate the efficacy of Fostera PRRS MLV vaccine in protecting against challenge with a heterologous field strain widely circulating in the swine herds of eastern Canada. Forty-six piglets were divided into 4 groups: nonvaccinated-nonchallenged; nonvaccinated-challenged; vaccinated-challenged; and vaccinated-nonchallenged. The animals were vaccinated at 23 d of age with Fostera PRRS and challenged 23 d later with a heterologous field strain of PRRSV (FMV12-1425619). Overall, the vaccine showed some beneficial effects in the challenged animals by reducing the severity of clinical signs and the viral load. A significant difference between nonvaccinated and vaccinated animals was detected for some parameters starting 11 to 13 d after challenge, which suggested that the cell-mediated immune response or other delayed responses could be more important than pre-existing PRRSV antibodies in vaccinated animals within the context of protection against heterologous strains. PMID:26732457

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

    PubMed

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

    2014-04-08

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

  14. Development and characterization of an infectious cDNA clone of the modified live virus vaccine strain of equine arteritis virus.

    PubMed

    Zhang, Jianqiang; Go, Yun Young; Huang, Chengjin M; Meade, Barry J; Lu, Zhengchun; Snijder, Eric J; Timoney, Peter J; Balasuriya, Udeni B R

    2012-08-01

    A stable full-length cDNA clone of the modified live virus (MLV) vaccine strain of equine arteritis virus (EAV) was developed. RNA transcripts generated from this plasmid (pEAVrMLV) were infectious upon transfection into mammalian cells, and the resultant recombinant virus (rMLV) had 100% nucleotide identity to the parental MLV vaccine strain of EAV. A single silent nucleotide substitution was introduced into the nucleocapsid gene (pEAVrMLVB), enabling the cloned vaccine virus (rMLVB) to be distinguished from parental MLV vaccine as well as other field and laboratory strains of EAV by using an allelic discrimination real-time reverse transcription (RT)-PCR assay. In vitro studies revealed that the cloned vaccine virus rMLVB and the parental MLV vaccine virus had identical growth kinetics and plaque morphologies in equine endothelial cells. In vivo studies confirmed that the cloned vaccine virus was very safe and induced high titers of neutralizing antibodies against EAV in experimentally immunized horses. When challenged with the heterologous EAV KY84 strain, the rMLVB vaccine virus protected immunized horses in regard to reducing the magnitude and duration of viremia and virus shedding but did not suppress the development of signs of EVA, although these were reduced in clinical severity. The vaccine clone pEAVrMLVB could be further manipulated to improve the vaccine efficacy as well as to develop a marker vaccine for serological differentiation of EAV naturally infected from vaccinated animals.

  15. Genetic variations of live attenuated plague vaccine strains (Yersinia pestis EV76 lineage) during laboratory passages in different countries.

    PubMed

    Cui, Yujun; Yang, Xianwei; Xiao, Xiao; Anisimov, Andrey P; Li, Dongfang; Yan, Yanfeng; Zhou, Dongsheng; Rajerison, Minoarisoa; Carniel, Elisabeth; Achtman, Mark; Yang, Ruifu; Song, Yajun

    2014-08-01

    Plague, one of the most devastating infectious diseases in human history, is caused by the bacterial species Yersinia pestis. A live attenuated Y. pestis strain (EV76) has been widely used as a plague vaccine in various countries around the world. Here we compared the whole genome sequence of an EV76 strain used in China (EV76-CN) with the genomes of Y. pestis wild isolates to identify genetic variations specific to the EV76 lineage. We identified 6 SNPs and 6 Indels (insertions and deletions) differentiating EV76-CN from its counterparts. Then, we screened these polymorphic sites in 28 other strains of EV76 lineage that were stored in different countries. Based on the profiles of SNPs and Indels, we reconstructed the parsimonious dissemination history of EV76 lineage. This analysis revealed that there have been at least three independent imports of EV76 strains into China. Additionally, we observed that the pyrE gene is a mutation hotspot in EV76 lineages. The fine comparison results based on whole genome sequence in this study provide better understanding of the effects of laboratory passages on the accumulation of genetic polymorphisms in plague vaccine strains. These variations identified here will also be helpful in discriminating different EV76 derivatives.

  16. Live attenuated measles and mumps viral strain-containing vaccines and hearing loss: Vaccine Adverse Event Reporting System (VAERS), United States, 1990--2003.

    PubMed

    Asatryan, Armenak; Pool, Vitali; Chen, Robert T; Kohl, Katrin S; Davis, Robert L; Iskander, John K

    2008-02-26

    Hearing loss (HL) is a known complication of wild measles and mumps viral infections. As vaccines against measles and mumps contain live attenuated viral strains, it is biologically plausible that in some individuals HL could develop as a complication of vaccination against measles and/or mumps. Our objectives for this study were: to find and describe all cases of HL reported in the scientific literature and to the US Vaccine Adverse Events Reporting System (VAERS) for the period 1990--2003; and to determine reporting rate of HL after live attenuated measles and/or mumps viral strain-containing vaccines (MMCV) administration. We searched published reports for cases of HL identified after vaccination with MMCV. We also searched for reports of HL after MMCV administration submitted to VAERS from 1990 through 2003 and determined the dose-adjusted reporting rate of HL. Our main outcome measure was reported cases of HL after immunization with MMCV which were classified as idiopathic. We found 11 published case reports of HL following MMCV. The review of the VAERS reports identified 44 cases of likely idiopathic sensorineural HL after MMCV administration. The onset of HL in the majority of VAERS and published cases was consistent with the incubation periods of wild measles and mumps viruses. Based on the annual usage of measles-mumps-rubella (MMR) vaccine, we estimated the reporting rate of HL to be 1 case per 6-8 million doses. Thus, HL following MMCV has been reported in the literature and to the VAERS. Further studies are needed to better understand if there is a causal relationship between MMCV and HL.

  17. Experience with live attenuated varicella vaccine (Oka strain) in healthy Japanese subjects; 10-year survey at pediatric clinic.

    PubMed

    Ozaki, T; Nishimura, N; Kajita, Y

    2000-05-08

    Live attenuated varicella vaccine (Oka strain, Biken Institute, Osaka, Japan) was administered to 973 healthy individuals over a 10-year period (1987-1997) at the pediatric clinic of Showa Hospital in Japan. We evaluated the relevant serological and clinical data, which were collected by questionnaire. Seroconversion by the immune adherence hemagglutination method was documented in 94% (805/860) of the initially seronegative subjects. Of the initially seropositive subjects, 56% (63/113) showed enhancement of antibody after vaccination. Reactions to the vaccine were generally insignificant, except for a rash at the injection site, seen in the first 3 days post-administration in 17% (41/241) of the recently vaccinated subjects. In March 1998, we conducted a survey of 559 of the initially seronegative subjects who had received the vaccine 0.6-10. 8 (mean 5.4) years earlier. Of these subjects, 21% (119/559) contracted breakthrough varicella. However, their symptoms were milder than those caused by natural varicella seen in unvaccinated children. Seroconversion was demonstrated in 92% (109/119) of these cases. The incidence of breakthrough disease decreased with a rise in postvaccination antibody titer to >==32. Four of the subjects (0.7% of 559) developed herpes zoster following vaccination, two of whom had earlier exhibited breakthrough varicella. Lesions in one case of zoster, without breakthrough varicella, appeared on the cervical dermatome at the injection site. The vaccine was safe and effective. However, there was a relatively high incidence of rash at the injection site with certain lot numbers used in recent years which warrants investigation.

  18. Risks associated with the use of live-attenuated vaccine poliovirus strains and the strategies for control and eradication of paralytic poliomyelitis.

    PubMed

    Pliaka, Vaia; Kyriakopoulou, Zaharoula; Markoulatos, Panayotis

    2012-05-01

    The Global Polio Eradication Initiative was launched in 1988 with the aim to eliminate paralytic poliomyelitis. Two effective vaccines are available: inactivated polio vaccine (IPV) and oral polio vaccine (OPV). Since 1964, OPV has been used instead of IPV in most countries due to several economic and biological advantages. However, in rare cases, the live-attenuated Sabin strains of OPV revert to neurovirulence and cause vaccine-associated paralytic poliomyelitis in vaccinees or lead to emergence of vaccine-derived poliovirus strains. Attenuating mutations and recombination events have been associated with the reversion of vaccine strains to neurovirulence. The substitution of OPV with an improved new-generation IPV and the availability of new specific drugs against polioviruses are considered as future strategies for outbreak control and the eradication of paralytic poliomyelitis worldwide.

  19. Clinical and serologic effects of Alice strain live attenuated influenza A (H3N2) virus vaccine in an adult population.

    PubMed

    Miller, L W; Togo, Y; Hornick, R B

    1975-12-30

    Alice strain live attenuated influenza A (H3N2) virus was evaluated in prison volunteers. By random double blind allocation, 94 volunteers received Alice strain vaccine (AS) intranasally and 97 received placebo. The vaccine was well tolerated, and there was no serious morbidity. The number, type, duration, and severity of symptoms was not significantly different between the vaccine and placebo groups. Seventy-five per cent of vaccines with initial HAI titers less than or equal to 1:8 had 4 fold or greater titer responses on day 30. Placebo recipients experienced no titer changes. The GMT among vaccinees increased from 23.5 prior to vaccination 59.7 30 days later. Surveillance activities failed to document influenza A (H3N2) infection in the volunteer population during a 6 month follow-up period. Additional studies on the protective effects of the vaccine are required before efficacy can be determined.

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

    DTIC Science & Technology

    2006-10-01

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

  1. Development and evaluation of an experimental vaccination program using a live avirulent Salmonella typhimurium strain to protect immunized chickens against challenge with homologous and heterologous Salmonella serotypes.

    PubMed Central

    Hassan, J O; Curtiss, R

    1994-01-01

    A stable live avirulent, genetically modified delta cya delta crp Salmonella typhimurium vaccine strain, chi 3985, was used in several vaccination strategies to evaluate its use in the control of Salmonella infection in chickens. Oral vaccination of chickens at 1 and at 14 days of age with 10(8) CFU of chi 3985 protected against invasion of spleen, ovary, and bursa of Fabricius and colonization of the ileum and cecum in chickens challenged with 10(6) CFU of virulent homologous Salmonella strains from group B. Chickens challenged with heterologous Salmonella strains from groups C, D, and E were protected against visceral invasion of spleen and ovary, while invasion of the bursa of Fabricius and colonization of ileum and cecum was reduced in vaccinated chickens. Oral vaccination at 2 and at 4 weeks of age induced an excellent protection against challenge with virulent group B Salmonella serotypes and very good protection against challenge with group D or E Salmonella serotypes, while protection against challenge with group C Salmonella serotypes was marginal but significant. Vaccination at 2 and at 4 weeks of age also protected vaccinated chickens against challenge with 10(8) CFU of highly invasive S. typhimurium or S. enteritidis strains. The protection of chickens vaccinated with chi 3985 against challenge with homologous and heterologous Salmonella serotypes is outstanding, and the complete protection against ovarian invasion in chickens challenged with 10(8) CFU of highly invasive S. typhimurium or S. enteritidis strains suggests that vaccination of chickens with chi 3985 can complement the present hygiene- and sanitation-based Salmonella control measures. This paper reports a breakthrough in the use of live avirulent vaccine to control Salmonella carriers in chickens. PMID:7960134

  2. Optimization of Plasmid Maintenance in the Attenuated Live Vector Vaccine Strain Salmonella typhi CVD 908-htrA†

    PubMed Central

    Galen, James E.; Nair, Jay; Wang, Jin Yuang; Wasserman, Steven S.; Tanner, Michael K.; Sztein, Marcelo B.; Levine, Myron M.

    1999-01-01

    The broad objective of the research presented here is to develop a noncatalytic plasmid maintenance system for the stabilization of multicopy expression plasmids encoding foreign antigens in a Salmonella typhi live-vector vaccine strain such as CVD 908-htrA. We have enhanced the maintenance of expression plasmids at two independent levels. First, we removed dependence upon balanced-lethal maintenance systems that involve catalytic enzymes expressed from multicopy plasmids; we accomplished this through incorporation into expression plasmids of a postsegregational killing system based on the noncatalytic hok-sok plasmid addiction system from the antibiotic resistance factor pR1. We also included at least one naturally occurring plasmid partition function in our expression plasmids, which eliminates random segregation of these plasmids, thereby enhancing their inheritance and stability; to accomplish this, we incorporated either the par locus from pSC101, the parA locus from pR1, or both. We monitored the stability of optimized expression plasmids within CVD 908-htrA by quantitating expression of a variant of green fluorescent protein (GFPuv) by using flow cytometry. In this report, we demonstrate the utility of this novel plasmid maintenance system in enhancing the stability of our expression plasmids and go on to show that as the copy number of stabilized plasmids increases, the toxicity of GFPuv synthesis also increases. The implications of these observations for the rational design of immunogenic and protective bacterial live vector vaccines are discussed. PMID:10569759

  3. Use of RapidChek® SELECT™ Salmonella to detect shedding of live attenuated Salmonella enterica serovar Typhi vaccine strains.

    PubMed

    Brenneman, Karen E; McDonald, Caitlin; Kelly-Aehle, Sandra M; Roland, Kenneth L; Curtiss, Roy

    2012-05-01

    Identification of individuals shedding Salmonella enterica serovar Typhi in stool is imperative during clinical trial safety evaluations. Recovery of live attenuated S. Typhi vaccine strains can be difficult because the mutations necessary for safety in humans often compromise survival in stringent selective enrichment media. RapidChek® SELECT™ Salmonella is a highly sensitive detection method for S. enterica species which utilizes a bacteriophage cocktail designed to reduce the growth of competitor microbes in mildly selective enrichment medium. Detection of Salmonella is enhanced by means of a Salmonella-specific antibody strip targeted to lipopolysaccharide. The RapidChek® SELECT™ Salmonella method was compared to conventional enrichment and plating methods to determine the most sensitive method for detecting attenuated S. Typhi strains in human stool samples. Although traditional enrichment strategies were more sensitive to the presence of wild-type S. Typhi, RapidChek® SELECT™ Salmonella was superior at detecting attenuated strains of S. Typhi. Strains containing a wide variety of attenuating mutations were detected with equal sensitivity as the wild type by RapidChek® SELECT™ Salmonella. The presence of Vi capsule or mutations which affected O-antigen synthesis (Δpmi, ΔgalE) did not decrease the sensitivity of the RapidChek® SELECT™ Salmonella assay.

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

    DTIC Science & Technology

    2006-08-10

    The culture and PCR results of all blood samples were negative. Results of real - time PCR from the inoculation site samples were positive for 41 (100...LVS vaccination, with real - time PCR being more sensitive than culture. Our data suggest that bacteremia does not occur after LVS vaccination in normal, healthy human volunteers.

  5. Immune Response to Vaccination with a Live Influenza Virus (H3N2) Vaccine (“Ann” Strain)

    PubMed Central

    Prévost, J. M.; Peetermans, J.; Lamy, F.; Huygelen, C.

    1973-01-01

    A live attenuated influenza virus (“Ann” strain) derived from A/England/878/69 was given intranasally to a group of volunteers, most of whom had already circulating antibodies against H3N2 viruses at the time of inoculation. There was a fourfold or higher increase of circulating hemagglutination-inhibiting antibodies in those volunteers who had relatively low initial titers. The response was lower in those with initially higher serum titers. The pattern of the serum neutralizing antibody response was very similar. The geometric means of the antineuraminidase antibodies were 67 and 118 pre- and postvaccination, respectively. All subjects showed a rise in local neutralizing antibodies in their nasal secretions with geometric means of 4 and 17 pre- and postvaccination, respectively. The levels of local antineuraminidase antibodies also rose in most subjects. In addition to the response to the homologous virus type, the antibody formation to the recent A/England/42/72 was measured in the sera and nasal secretions of some subjects. There was a clearcut response in most of the sera and in all of the secretions examined. The stimulation of circulating lymphocytes was measured in 6 volunteers. All volunteers showed a temporary stimulation. The stimulation index ranged between 2.5 and 28.5. PMID:4729931

  6. Persistence of cell-mediated immunity three decades after vaccination with the live vaccine strain of Francisella tularensis

    PubMed Central

    Eneslätt, Kjell; Rietz, Cecilia; Rydén, Patrik; Stöven, Svenja; House, Robert V.; Wolfraim, Lawrence A.; Tärnvik, Arne; Sjöstedt, Anders

    2012-01-01

    Summary The efficacy of many vaccines against intracellular bacteria depends on the generation of cell-mediated immunity, but studies to determine the duration of immunity are usually confounded by re-exposure. The causative agent of tularemia, Francisella tularensis, is rare in most areas and, therefore, tularemia vaccination is an interesting model for studies of the longevity of vaccine-induced cell-mediated immunity. Here lymphocyte proliferation and cytokine production in response to F. tularensis were assayed in two groups of 16 individuals, vaccinated 1-3 or 27-34 years previously. As compared to naïve individuals, vaccinees of both groups showed higher proliferative responses and, out of 17 cytokines assayed, higher levels of MIP-1β, IFN-γ, IL-10, and IL-5 in response to recall stimulation. The responses were very similar in the two groups of vaccinees. A statistical model was developed to predict the immune status of the individuals and by use of two parameters, proliferative responses and levels of IFN-γ, 91.1% of the individuals were correctly classified. Using flow cytometry analysis, we demonstrated that during recall stimulation, expression of IFN-γ by CD4+CCR7+, CD4+CD62L+, CD8+CCR7+, and CD8+CD62L+ cells significantly increased in samples from vaccinated donors. In conclusion, cell-mediated immunity was found to persist three decades after tularemia vaccination without evidence of decline. PMID:21442618

  7. Complete genome analysis of three live attenuated Rinderpest virus vaccine strains derived through serial passages in different culture systems.

    PubMed

    Jeoung, Hye-Young; Lee, Myoung-Heon; Yeh, Jung-Yong; Lim, Ji-Ae; Lim, Seong-In; Oem, Jae-Ku; Song, Jae-Young; Lee, Won-Ha; Park, Jong-Hwan; An, Dong-Jun

    2012-12-01

    The genomes of three South Korean Rinderpest virus vaccine strains (L72, LA77, and LA96) were analyzed in order to investigate their genetic variability. These three vaccine strains were all derived from the same virus strain origin (Fusan) through repeated passages in different culture systems. The full genome length of the three strains was 15,882 nucleotides, and the sequence similarity between the three South Korean RPV strains at the nucleotide level was 98.1 to 98.9%. The genetic distance between Nakamura III, L72, LA77, LA96, and LATC06 and the Kabete strain was greater than that between the Fusan and Kabete strains for the P, V, and C genes. The difference in pathogenicity among these strains might be due to the V gene, which has a positive (>1) selection ratio based on the analysis of synonymous (dS) and nonsynonymous (dN) substitution rates (dN/dS ratio [ω]).

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

    PubMed

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

    2014-01-01

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

  9. Protective immune response of chickens to oral vaccination with thermostable live Fowlpox virus vaccine (strain TPV-1) coated on oiled rice.

    PubMed

    Wambura, Philemon N; Godfrey, S K

    2010-03-01

    The objective of the present study was to develop and evaluate a local vaccine (strain TPV-1) against Fowl pox (FP) in chickens. Two separate groups of chickens were vaccinated with FP vaccine through oral (coated on oiled rice) and wing web stab routes, respectively. The results showed that the haemagglutination-inhibition (HI) antibody titres in both vaccinated groups were comparable and significantly higher (P < 0.05) than the control chickens. It was further revealed that 14 days after vaccination HI GMT of > or =2 log(2) was recorded in chickens vaccinated by oral and wing web stab routes whereas 35 days after vaccination the HI antibody titres reached 5.6 log(2) and 6.3 log(2), respectively. Moreover, in both groups the birds showed 100% protection against challenge virus at 35 days after vaccination. The findings from the present study have shown that oral route is equally effective as wing web stab route for vaccination of chickens against FP. However, the oral route can be used in mass vaccination of birds thus avoid catching individual birds for vaccination. It was noteworthy that strain TPV-1 virus could be propagated by a simple allantoic cavity inoculation and harvesting of allantoic fluid where it survived exposure at 57 degrees C for 2 hours. If the oral vaccination technique is optimized it may be used in controlling FP in scavenging and feral chickens. In conclusion, the present study has shown that FP vaccine (strain TPV-1) was safe, thermostable, immunogenic and efficacious in vaccinated chickens.

  10. An infectious cDNA clone of the poliovirus Sabin strain could be used as a stable repository and inoculum for the oral polio live vaccine.

    PubMed

    Kohara, M; Abe, S; Kuge, S; Semler, B L; Komatsu, T; Arita, M; Itoh, H; Nomoto, A

    1986-05-01

    Viruses were recovered from HeLa S3 cells and African green monkey kidney (AGMK) cells transfected with an infectious cDNA clone of poliovirus vaccine Sabin 1 strain. The viruses recovered from the different DNA-transfected cells were tested for the biological characteristics of temperature sensitivity (rct marker), plaque size, and bicarbonate concentration dependency (d marker). The results revealed that the above properties were similar to those obtained from tests on the Sabin 1 vaccine reference strain. The recovered viruses and the vaccine reference virus were passaged in AGMK cells at an elevated temperature of 37.5 degrees, and the passaged isolates were tested for the rct marker. The virus recovered from AGMK cells had the most stable rct phenotype while the virus from HeLa S3 cells had a similar stability to that of the reference virus, suggesting that the virus from AGMK cells would be more suitable as a vaccine strain than the other two viruses. Furthermore, an infectious cDNA clone of high specific infectivity, constructed by introducing SV40 large T antigen into the plasmid, was used for production of high titers of virus after transfection. The results of in vitro biological tests on the recovered virus suggested that virus produced in the transfected AGMK cells also had the high quality that is desirable in vaccine stocks. Monkey neurovirulence tests performed with these recovered viruses revealed that the recovered viruses were weakly neurovirulent, similar to the vaccine reference virus. The infectious cDNA clone of the poliovirus vaccine strain could therefore be used to generate a possible inoculum of the oral polio live vaccine. Our findings strongly suggest that an infectious cDNA clone of poliovirus RNA may be used to preserve the constancy and quality of the present seed viruses of the Sabin 1 vaccine strain.

  11. Protection induced by a glycoprotein E-deleted bovine herpesvirus type 1 marker strain used either as an inactivated or live attenuated vaccine in cattle

    PubMed Central

    2014-01-01

    Background Bovine herpesvirus type 1 (BoHV-1) is the causative agent of respiratory and genital tract infections; causing a high economic loss in all continents. Use of marker vaccines in IBR eradication programs is widely accepted since it allows for protection of the animals against the disease while adding the possibility of differentiating vaccinated from infected animals. The aim of the present study was the development and evaluation of safety and efficacy of a glycoprotein E-deleted (gE-) BoHV-1 marker vaccine strain (BoHV-1ΔgEβgal) generated by homologous recombination, replacing the viral gE gene with the β-galactosidase (βgal) gene. Results In vitro growth kinetics of the BoHV-1ΔgEβgal virus was similar to BoHV-1 LA. The immune response triggered by the new recombinant strain in cattle was characterized both as live attenuated vaccine (LAV) and as an inactivated vaccine. BoHV-1ΔgEβgal was highly immunogenic in both formulations, inducing specific humoral and cellular immune responses. Antibody titers found in animals vaccinated with the inactivated vaccine based on BoHV-1ΔgEβgal was similar to the titers found for the control vaccine (BoHV-1 LA). In the same way, titers of inactivated vaccine groups were significantly higher than any of the LAV immunized groups, independently of the inoculation route (p < 0.001). Levels of IFN-γ were significantly higher (p < 0.001) in those animals that received the LAV compared to those that received the inactivated vaccine. BoHV-1ΔgEβgal exhibited an evident attenuation when administered as a LAV; no virus was detected in nasal secretions of vaccinated or sentinel animals during the post-vaccination period. BoHV-1ΔgEβgal, when used in either formulation, elicited an efficient immune response that protected animals against challenge with virulent wild-type BoHV-1. Also, the deletion of the gE gene served as an immunological marker to differentiate vaccinated animals from infected animals. All

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

    PubMed

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

    2006-09-11

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  14. Efficiency of live attenuated and inactivated rabies viruses in prophylactic and post exposure vaccination against the street virus strain.

    PubMed

    Huang, F; Ahmad, W; Duan, M; Liu, Z; Guan, Z; Zhang, M; Qiao, B; Li, Y; Song, Y; Song, Y; Chen, Y; Amjad Ali, M

    2015-06-01

    Rabies remains an enigmatic and widely discussed global infectious disease and causes an increasing number of deaths. The currently used highly effective prophylactic and post exposure (p.e.) vaccination depends solely upon inexpensive, effective and safe vaccines to counteract the spread of the disease. In this study, the potential of an attenuated Chinese rabies vaccine (SRV9) strain in prophylactic and p.e. vaccination against the street strain of rabies virus (RV) was evaluated in mice. Prophylactic vaccination consisting of one intramuscular (i.m.) dose of SRV9 protected 100% of mice from intracerebral (i.c.) challenge with a lethal dose of the street virus. The latter was detected in the brain of mice at day 6 post challenge by RT-PCR. Post exposure vaccination was performed at days 1, 2, 3, 4, 5 and 6 post infection (p.i.) with either SRV9 or inactivated rabies vaccine. The survival rates after i.m. inoculation of SRV9 at the indicated days were 70%, 50%, 30%, 20%, 10%, and 0%, respectively; the corresponding survival rates for the inactivated rabies vaccine were 30%, 20%, 10%, 0%, 0%, and 0%, respectively. However, 100%, 90%, 70%, 50%, 20%, 10%, and 10% of mice survived after i.c. inoculation of SRV9 at the indicated days. The increased permeability of the blood-brain barrier and the infiltration of CD19+ B cells into the central nervous system after i.c. inoculation of SRV9 are regarded as prerequisites for the clearance of the street virus. The obtained data suggest that SRV9 is a promising candidate for prophylactic and p.e. vaccination against rabies infection and that it exhibits a potential for the control of rabies in China.

  15. Mycoplasma gallisepticum: Control by live attenuated vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Stable Salmonella live vaccine strains with two or more attenuating mutations and any desired level of attenuation.

    PubMed

    Linde, K; Beer, J; Bondarenko, V

    1990-06-01

    Mutants optimally attenuated for highly susceptible hosts and protecting after a single oral vaccination are often overattenuated for host species being less susceptible. Therefore, to select vaccine strains optimally attenuated for the particular host species it is essential that a range of mutants with graded levels of attenuation be provided so as to permit lesser susceptibility to be compensated for by a correspondingly lower level of attenuation. This, while guaranteeing the stability through two-marker or multi-marker attenuation, can be suitably accomplished by slightly to moderately virulence-reducing mutations. Aspartic acid auxotrophy and, in particular, 'metabolic drift' mutations, possibly by additionally incorporating antiepidemic markers, are adopted for the mouse model to demonstrate stepwise production of S. typhimurium and S. typhi vaccine candidate strains with graded attenuation or any level of attenuation desirable. It is emphasized that this basic approach is relevant to practice.

  17. Molecular typing of Japanese field isolates and live commercial vaccine strain of Mycoplasma synoviae using improved pulsed-field gel electrophoresis and vlhA gene sequencing.

    PubMed

    Harada, Kazuki; Kijima-Tanaka, Mayumi; Uchiyama, Mariko; Yamamoto, Tomoko; Oishi, Koji; Arao, Megumi; Takahashi, Toshio

    2009-12-01

    In the present study, pulsed-field gel electrophoresis (PFGE) and vlhA gene sequence analysis were applied and verified for typing the Mycoplasma synoviae live vaccine MS-H strain and field isolates from diseased chickens in Japan. The previously published PFGE protocol using SmaI digestion could not allow the discrimination of two of the 11 M. synoviae field isolates from the vaccine strain and had relatively low discrimination power (D = 0.885). On the other hand, our new PFGE protocols using BlnI and BamHI digestions as well as the vlhA sequence analysis allowed the discrimination of all 11 M. synoviae field isolates from the vaccine strain. In addition, these PFGE protocols using BlnI and BamHI digestions generated unique fragment patterns in epidemiologically unrelated isolates, including those with identical SmaI-digested patterns or vlhA gene sequences (D = 0.987 and 1.000, respectively), and generated indistinguishable or closely related patterns in epidemiologically related isolates. Therefore, we believe that they would be useful tools to determine whether M. synoviae clinical isolates from diseased chickens are derived from the vaccine strain or wild-type strain and to further elucidate the epidemiology of M. synoviae infection.

  18. Next-Generation Bacillus anthracis Live Attenuated Spore Vaccine Based on the htrA(-) (High Temperature Requirement A) Sterne Strain.

    PubMed

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

    2016-01-06

    Anthrax is a lethal disease caused by the gram-positive spore-producing bacterium Bacillus anthracis. Live attenuated vaccines, such as the nonencapsulated Sterne strain, do not meet the safety standards mandated for human use in the Western world and are approved for veterinary purposes only. Here we demonstrate that disrupting the htrA gene, encoding the chaperone/protease HtrA (High Temperature Requirement A), in the virulent Bacillus anthracis Vollum strain results in significant virulence attenuation in guinea pigs, rabbits and mice, underlying the universality of the attenuated phenotype associated with htrA knockout. Accordingly, htrA disruption was implemented for the development of a Sterne-derived safe live vaccine compatible with human use. The novel B. anthracis SterneΔhtrA strain secretes functional anthrax toxins but is 10-10(4)-fold less virulent than the Sterne vaccine strain depending on animal model (mice, guinea pigs, or rabbits). In spite of this attenuation, double or even single immunization with SterneΔhtrA spores elicits immune responses which target toxaemia and bacteremia resulting in protection from subcutaneous or respiratory lethal challenge with a virulent strain in guinea pigs and rabbits. The efficacy of the immune-protective response in guinea pigs was maintained for at least 50 weeks after a single immunization.

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

    PubMed

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

    1980-01-01

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

  20. Complete Genome Analysis of Three Live Attenuated Rinderpest Virus Vaccine Strains Derived through Serial Passages in Different Culture Systems

    PubMed Central

    Jeoung, Hye-Young; Lee, Myoung-Heon; Yeh, Jung-Yong; Lim, Ji-Ae; Lim, Seong-in; Oem, Jae-Ku; Song, Jae-Young; Lee, Won-Ha; Park, Jong-Hwan

    2012-01-01

    The genomes of three South Korean Rinderpest virus vaccine strains (L72, LA77, and LA96) were analyzed in order to investigate their genetic variability. These three vaccine strains were all derived from the same virus strain origin (Fusan) through repeated passages in different culture systems. The full genome length of the three strains was 15,882 nucleotides, and the sequence similarity between the three South Korean RPV strains at the nucleotide level was 98.1 to 98.9%. The genetic distance between Nakamura III, L72, LA77, LA96, and LATC06 and the Kabete strain was greater than that between the Fusan and Kabete strains for the P, V, and C genes. The difference in pathogenicity among these strains might be due to the V gene, which has a positive (>1) selection ratio based on the analysis of synonymous (dS) and nonsynonymous (dN) substitution rates (dN/dS ratio [ω]). PMID:23118448

  1. Evaluation of a Salmonella Strain Lacking the Secondary Messenger C-di-GMP and RpoS as a Live Oral Vaccine

    PubMed Central

    García, Begoña; Gil, Carmen; García-Ona, Enrique; Burgui, Saioa; Casares, Noelia; Hervás-Stubbs, Sandra; Lasarte, Juan José; Lasa, Iñigo

    2016-01-01

    Salmonellosis is one of the most important bacterial zoonotic diseases transmitted through the consumption of contaminated food, with chicken and pig related products being key reservoirs of infection. Although numerous studies on animal vaccination have been performed in order to reduce Salmonella prevalence, there is still a need for an ideal vaccine. Here, with the aim of constructing a novel live attenuated Salmonella vaccine candidate, we firstly analyzed the impact of the absence of cyclic-di-GMP (c-di-GMP) in Salmonella virulence. C-di-GMP is an intracellular second messenger that controls a wide range of bacterial processes, including biofilm formation and synthesis of virulence factors, and also modulates the host innate immune response. Our results showed that a Salmonella multiple mutant in the twelve genes encoding diguanylate cyclase proteins that, as a consequence, cannot synthesize c-di-GMP, presents a moderate attenuation in a systemic murine infection model. An additional mutation of the rpoS gene resulted in a synergic attenuating effect that led to a highly attenuated strain, referred to as ΔXIII, immunogenic enough to protect mice against a lethal oral challenge of a S. Typhimurium virulent strain. ΔXIII immunogenicity relied on activation of both antibody and cell mediated immune responses characterized by the production of opsonizing antibodies and the induction of significant levels of IFN-γ, TNF-α, IL-2, IL-17 and IL-10. ΔXIII was unable to form a biofilm and did not survive under desiccation conditions, indicating that it could be easily eliminated from the environment. Moreover, ΔXIII shows DIVA features that allow differentiation of infected and vaccinated animals. Altogether, these results show ΔXIII as a safe and effective live DIVA vaccine. PMID:27537839

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. A live attenuated human metapneumovirus vaccine strain provides complete protection against homologous viral infection and cross-protection against heterologous viral infection in BALB/c mice.

    PubMed

    Liu, Ping; Shu, Zhou; Qin, Xian; Dou, Ying; Zhao, Yao; Zhao, Xiaodong

    2013-08-01

    A live attenuated vaccine candidate strain (M2) of human metapneumovirus (hMPV) was generated by removing the N-linked carbohydrate at amino acid 172 in the fusion (F) protein. Previously, replication of M2 in mouse lungs could be detected by molecular assays but not by viral titration. In the present study, the protective effects of M2 against infection by homologous or heterologous viruses were evaluated in BALB/c mice. Immunization with M2 produced a high titer of serum virus-neutralizing antibodies in BALB/c mice at 4 and 8 weeks postimmunization, with the titers against the homologous virus being higher than those against the heterologous virus. Challenges at 4 and 8 weeks postinoculation with M2 or wild-type virus led to no replication when mice were challenged with a homologous virus and extremely reduced replication when mice were challenged with a heterologous virus, as determined by the detection of viral genomic RNA copies in the lungs, as well as significantly milder pulmonary pathology. Thus, M2, with only one N-linked carbohydrate removed in the F protein, provides complete protection from homologous virus infection and substantial cross-protection from heterologous virus infection for at least 56 days after inoculation. This vaccine strain may therefore be a candidate for further preclinical study. Furthermore, this attenuating strategy (changing the glycosylation of a major viral protein) may be useful in the development of other viral vaccines.

  4. Safety and immunogenicity of single dose live attenuated varicella vaccine (VR 795 Oka strain) in healthy Indian children: a randomized controlled study.

    PubMed

    Mitra, Monjori; Faridi, Mma; Ghosh, Apurba; Shah, Nitin; Shah, Raju; Chaterjee, Suparna; Narang, Manish; Bhattacharya, Nisha; Bhat, Gandhali; Choudhury, Harish; Kadhe, Ganesh; Mane, Amey; Roy, Sucheta

    2015-01-01

    Varicella, an acute viral systemic infection that may cause lifelong latent infection with the potential for causing clinical reactivation, may be prevented by immunization. The present study was an open label, randomized, controlled, phase III, multicentre trial, conducted to evaluate and compare the safety, tolerability and immunogenicity of a freeze dried live attenuated Oka strain Varicella Vaccine (VR 795 Oka strain) with Varilrix (Oka-RIT strain) in children. A total of 268 healthy Indian children aged 12 months to 12 y with baseline VZV IgG antibody (<100 mIU/ mL) were enrolled, and 256 children completed the study. The extent of rise of VZV IgG antibody titer assessed as 3-fold and 4-fold rise from baseline was found to be significantly higher (89.1% and 85.2%) in the test group as compared to control group (73.4% and 61.7%). The post-vaccination GMT of the test group was significantly higher (112.5 mIU/mL) as compared with the control group (67.8 mIU/mL) (P < 0.001). The seroconversion rate considering the 5 gp ELISA units/ml equivalent to 10mIU/ml were similar in the control (96.5%) and the test (98.3%) groups. The adverse events were not different in the control and test groups (P > 0.05). The test live attenuated vaccine was found to be highly immunogenic, safe and comparable to Varilrix used in control arm.

  5. Live attenuated influenza vaccine strains elicit a greater innate immune response than antigenically-matched seasonal influenza viruses during infection of human nasal epithelial cell cultures.

    PubMed

    Fischer, William A; Chason, Kelly D; Brighton, Missy; Jaspers, Ilona

    2014-03-26

    Influenza viruses are global pathogens that infect approximately 10-20% of the world's population each year. Vaccines, including the live attenuated influenza vaccine (LAIV), are the best defense against influenza infections. The LAIV is a novel vaccine that actively replicates in the human nasal epithelium and elicits both mucosal and systemic protective immune responses. The differences in replication and innate immune responses following infection of human nasal epithelium with influenza seasonal wild type (WT) and LAIV viruses remain unknown. Using a model of primary differentiated human nasal epithelial cell (hNECs) cultures, we compared influenza WT and antigenically-matched cold adapted (CA) LAIV virus replication and the subsequent innate immune response including host cellular pattern recognition protein expression, host innate immune gene expression, secreted pro-inflammatory cytokine production, and intracellular viral RNA levels. Growth curves comparing virus replication between WT and LAIV strains revealed significantly less infectious virus production during LAIV compared with WT infection. Despite this disparity in infectious virus production the LAIV strains elicited a more robust innate immune response with increased expression of RIG-I, TLR-3, IFNβ, STAT-1, IRF-7, MxA, and IP-10. There were no differences in cytotoxicity between hNEC cultures infected with WT and LAIV strains as measured by basolateral levels of LDH. Elevated levels of intracellular viral RNA during LAIV as compared with WT virus infection of hNEC cultures at 33°C may explain the augmented innate immune response via the up-regulation of pattern recognition receptors and down-stream type I IFN expression. Taken together our results suggest that the decreased replication of LAIV strains in human nasal epithelial cells is associated with a robust innate immune response that differs from infection with seasonal influenza viruses, limits LAIV shedding and plays a role in the silent

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

    PubMed

    2003-01-01

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

  7. An improved Francisella tularensis Live Vaccine Strain (LVS) is well tolerated and highly immunogenic when administered to rabbits in escalating doses using various immunization routes

    PubMed Central

    Pasetti, Marcela F.; Cuberos, Lilian; Horn, Thomas L.; Shearer, Jeffry D.; Matthews, Stephen J.; House, Robert V.; Sztein, Marcelo B.

    2008-01-01

    Tularemia is a severe disease for which there is no licensed vaccine. An attenuated F. tularensis live vaccine strain (LVS) was protective when administered to humans but safety concerns precluded its licensure and use in large scale immunization. An improved F. tularensis LVS preparation was produced under current Good Manufacturing Practice (cGMP) guidelines for evaluation in clinical trials. Preclinical safety, tolerability and immunogenicity were investigated in rabbits that received LVS in escalating doses (1x105 to 1x109 CFU) by the intradermal, subcutaneous or percutaneous (scarification) route. This improved LVS formulation was well tolerated at all doses; no death or adverse clinical signs were observed and necropsies showed no signs of pathology. No live organisms were detected in liver or spleen. Transient local reactogenicity was observed after scarification injection. Erythema and edema developed after intradermal injection in the highest dose cohorts. High levels of F. tularensis-specific IgM, IgG and IgA developed early after immunization, in a dose-dependent fashion. Scarification elicited higher levels of IgA. Antibodies elicited by LVS also recognized F. tularensis Schu-S4 antigens and there was a significant correlation between antibody titers measured against both LVS and Schu-S4. The ELISA titers also correlated closely with those measured by microagglutination. This is the first report describing comprehensive toxicological and immunological studies of F. tularensis LVS in rabbits. This animal model, which closely resembles human disease, proved adequate to assess safety and immunogenicity of F. tularensis vaccine candidates. This new LVS vaccine preparation is being evaluated in human clinical studies. PMID:18308432

  8. Virus recovery rates for wild-type and live-attenuated vaccine strains of African horse sickness virus serotype 7 in orally infected South African Culicoides species.

    PubMed

    Venter, G J; Paweska, J T

    2007-12-01

    Previously reported virus recovery rates from Culicoides (Avaritia) imicola Kieffer and Culicoides (Avaritia) bolitinos Meiswinkel (Diptera, Ceratopogonidae) orally infected with vaccine strain of African horse sickness virus serotype 7 (AHSV-7) were compared with results obtained from concurrently conducted oral infections with five recent AHSV-7 isolates from naturally infected horses from various localities in South Africa. Culicoides were fed sheep bloods spiked with 10(7.6) TCID(50)/mL of a live-attenuated vaccine strain AHSV-7, and with five field isolates in which virus titre in the bloodmeals ranged from 10(7.1) to 10(8.2) TCID(50)/mL). After an extrinsic incubation of 10 days at 23.5 degrees C, virus recovery rates were significantly higher in C. imicola (13.3%) and C. bolitinos (4.2%) infected with the live-attenuated virus than in midges infected with any of the field isolates. The virus recovery rates for the latter groups ranged from 0% to 9.5% for C. imicola and from 0% to 1.5% for C. bolitinos. The C. imicola population at Onderstepoort was significantly more susceptible to infection with AHSV-7 isolated at Onderstepoort than to the virus strains isolated from other localities. Results of this study suggest that tissue culture attenuation of AHSV-7 does not reduce its ability to orally infect competent Culicoides species and may even lead to enhanced replication in the vector. Furthermore, oral susceptibility in a midge population appears to vary for geographically distinct isolates of AHSV-7.

  9. A modified live PRRSV vaccine and the pathogenic parent strain induce regulatory T cells in pigs naturally infected with Mycoplasma hyopneumoniae.

    PubMed

    LeRoith, T; Hammond, S; Todd, S M; Ni, Y; Cecere, T; Pelzer, K D

    2011-04-15

    The lack of heterologous protection by porcine reproductive and respiratory syndrome virus (PRRSV) vaccines is currently a major problem in the field. Heterologous protection by PRRS vaccines depends on the ability of the vaccine to induce an interferon gamma (IFN-γ) response. One mechanism by which the virus evades the immune system is by activating regulatory T cells (T(regs)), resulting in induction of interleukin 10 rather than IFN-γ. Our hypothesis that current PRRS vaccines do not differ from pathogenic strains in the ability to induce T(regs) was tested by inoculating three groups of pigs with two pathogenic viruses and an attenuated vaccine strain and evaluating the number of T(regs) in peripheral blood mononuclear cells. Before inoculation, the pigs, although vaccinated became infected naturally with Mycoplasma hyopneumoniae before shipment to our research facility. Our results show that the PRRSV vaccine strain and parent strain are equally able to induce T(regs) in pigs naturally infected with M. hyopneumoniae. Pigs in the vaccine and PRRSV groups had higher lung lesion scores than pigs in the control groups. The results suggest that the exacerbation M. hyopneumoniae respiratory disease may be due to the ability of PRRSV vaccination and viral infection to induce regulatory T cells.

  10. Evaluation and improvement of a single nucleotide polymorphism-based PCR assay for rapid differentiation of live attenuated vaccine strains from field isolates of Erysipelothrix rhusiopathiae.

    PubMed

    Zhu, Weifeng; Li, Jingtao; Wang, Ya; Kang, Chao; Jin, Meilin; Chen, Huanchun

    2016-11-01

    A single nucleotide polymorphism-based PCR assay has been developed to differentiate the attenuated vaccine strain used in Japan from field isolates of Erysipelothrix rhusiopathiae found in pigs. However, this assay has been evaluated with only Japanese strains and isolates; therefore, it is unknown whether it could be used in other countries with E. rhusiopathiae strains and isolates of different genetic backgrounds. In our study, the PCR assay was evaluated using Chinese E. rhusiopathiae vaccine strains and field isolates. The PCR assay was able to differentiate the attenuated vaccine strains from the field isolates of E. rhusiopathiae in China but with a pattern different from that observed in Japan (only a single nucleotide polymorphism was detected in the Chinese vaccine strains compared with 5 in the Japanese vaccine strains). Importantly, either a DNA polymerase without 3' to 5' exonuclease activity or an exo(+) polymerase with an antibody inhibiting the proofreading activity was required. In conclusion, after evaluation and improvement, this fast differentiation assay can be extended from Japan to China.

  11. Live attenuated hepatitis A vaccines developed in China.

    PubMed

    Xu, Zhi-Yi; Wang, Xuan-Yi

    2014-01-01

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

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

    PubMed

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

    2013-02-04

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

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

    PubMed

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

    2015-11-01

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

  14. Genetically Engineered, Live Attenuated Vaccines Protect Nonhuman Primates Against Aerosol Challenge with a Virulent IE Strain of Venezuelan Equine Encephalitis Virus

    DTIC Science & Technology

    2005-01-21

    Vaccine 23 (2005) 3139–3147 Genetically engineered, live, attenuated vaccines protect nonhuman primates against aerosol challenge with a virulent IE...Prattb, Michael D. Parkerb a Center for Aerobiological Sciences, U.S. Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort...Received 27 August 2004; received in revised form 22 December 2004; accepted 23 December 2004 Available online 21 January 2005 Abstract d w h o a w s f P

  15. Attenuated live cholera vaccine strain CVD 103-HgR elicits significantly higher serum vibriocidal antibody titers in persons of blood group O.

    PubMed Central

    Lagos, R; Avendaño, A; Prado, V; Horwitz, I; Wasserman, S; Losonsky, G; Cryz, S; Kaper, J B; Levine, M M

    1995-01-01

    Persons of blood group O are at increased risk of developing cholera gravis. In a randomized, placebo-controlled, double-blind safety-immunogenicity trial of live oral cholera vaccine CVD 103-HgR in 5- to 9-year-old Chilean children, vibriocidal antibody seroconversion (74% overall) did not differ by blood group. However, the reciprocal geometric mean titer (GMT) in blood group O vaccines (GMT = 486) was higher than that in non-O vaccines (GMT = 179) (P < 0.02). PMID:7822046

  16. Attenuated live cholera vaccine strain CVD 103-HgR elicits significantly higher serum vibriocidal antibody titers in persons of blood group O.

    PubMed

    Lagos, R; Avendaño, A; Prado, V; Horwitz, I; Wasserman, S; Losonsky, G; Cryz, S; Kaper, J B; Levine, M M

    1995-02-01

    Persons of blood group O are at increased risk of developing cholera gravis. In a randomized, placebo-controlled, double-blind safety-immunogenicity trial of live oral cholera vaccine CVD 103-HgR in 5- to 9-year-old Chilean children, vibriocidal antibody seroconversion (74% overall) did not differ by blood group. However, the reciprocal geometric mean titer (GMT) in blood group O vaccines (GMT = 486) was higher than that in non-O vaccines (GMT = 179) (P < 0.02).

  17. The delicate balance in genetically engineering live vaccines

    PubMed Central

    Galen, James E.; Curtiss, Roy

    2014-01-01

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

  18. The delicate balance in genetically engineering live vaccines.

    PubMed

    Galen, James E; Curtiss, Roy

    2014-07-31

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

  19. Temporal Transcriptional Response during Infection of Type II Alveolar Epithelial Cells with Francisella tularensis Live Vaccine Strain (LVS) Supports a General Host Suppression and Bacterial Uptake by Macropinocytosis*

    PubMed Central

    Bradburne, Christopher E.; Verhoeven, Anne B.; Manyam, Ganiraju C.; Chaudhry, Saira A.; Chang, Eddie L.; Thach, Dzung C.; Bailey, Charles L.; van Hoek, Monique L.

    2013-01-01

    Pneumonic tularemia is caused by inhalation of Francisella tularensis, one of the most infectious microbes known. We wanted to study the kinetics of the initial and early interactions between bacterium and host cells in the lung. To do this, we examined the infection of A549 airway epithelial cells with the live vaccine strain (LVS) of F. tularensis. A549 cells were infected and analyzed for global transcriptional response at multiple time points up to 16 h following infection. At 15 min and 2 h, a strong transcriptional response was observed including cytoskeletal rearrangement, intracellular transport, and interferon signaling. However, at later time points (6 and 16 h), very little differential gene expression was observed, indicating a general suppression of the host response consistent with other reported cell lines and murine tissues. Genes for macropinocytosis and actin/cytoskeleton rearrangement were highly up-regulated and common to the 15 min and 2 h time points, suggesting the use of this method for bacterial entry into cells. We demonstrate macropinocytosis through the uptake of FITC-dextran and amiloride inhibition of Francisella LVS uptake. Our results suggest that macropinocytosis is a potential mechanism of intracellular entry by LVS and that the host cell response is suppressed during the first 2–6 h of infection. These results suggest that the attenuated Francisella LVS induces significant host cell signaling at very early time points after the bacteria's interaction with the cell. PMID:23322778

  20. Comparison of Molecular and Biological Characteristics of a Modified Live Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Vaccine (Ingelvac PRRS MLV), the Parent Strain of the Vaccine (ATCC VR2332), ATCC VR2385, and Two Recent Field Isolates of PRRSV

    PubMed Central

    Opriessnig, T.; Halbur, P. G.; Yoon, K.-J.; Pogranichniy, R. M.; Harmon, K. M.; Evans, R.; Key, K. F.; Pallares, F. J.; Thomas, P.; Meng, X. J.

    2002-01-01

    The objectives of this study were to compare the molecular and biological characteristics of recent porcine reproductive and respiratory syndrome virus (PRRSV) field isolates to those of a modified live virus (MLV) PRRS vaccine and its parent strain. One hundred seventeen, 4-week-old pigs were randomly assigned to six groups. Group 1 (n = 20) served as sham-inoculated negative controls, group 2 (n = 19) was inoculated with Ingelvac PRRS MLV vaccine, group 3 (n = 20) was inoculated with the parent strain of the vaccine (ATCC VR2332), group 4 (n = 19) was inoculated with vaccine-like PRRSV field isolate 98-38803, group 5 (n = 19) was inoculated with PRRSV field isolate 98-37120, and group 6 (n = 20) was inoculated with known high-virulence PRRSV isolate ATCC VR2385. The levels of severity of gross lung lesions (0 to 100%) among the groups were significantly different at both 10 (P < 0.0001) and 28 days postinoculation (p.i.) (P = 0.002). At 10 days p.i., VR2332 (26.5% ± 4.64%) and VR2385 (36.4% ± 6.51%) induced gross lesions of significantly greater severity than 98-38803 (0.0% ± 0.0%), 98-37120 (0.8% ± 0.42%), Ingelvac PRRS MLV (0.9% ± 0.46%), and negative controls (2.3% ± 1.26%). At 28 days p.i., 98-37120 (17.2% ± 6.51%) induced gross lesions of significantly greater severity than any of the other viruses. Analyses of the microscopic-interstitial-pneumonia-lesion scores (0 to 6) revealed that VR2332 (2.9 ± 0.23) and VR2385 (3.1 ± 0.35) induced significantly more severe lesions at 10 days p.i. At 28 days p.i., VR2385 (2.5 ± 0.27), VR2332 (2.3 ± 0.21), 98-38803 (2.6 ± 0.29), and 98-37120 (3.0 ± 0.41) induced significantly more severe lesions than Ingelvac PRRS MLV (0.7 ± 0.17) and controls (0.7 ± 0.15). The molecular analyses and biological characterizations suggest that the vaccine-like isolate 98-38803 (99.5% amino acid homology based on the ORF5 gene) induces microscopic pneumonia lesions similar in type to, but different in severity and time of

  1. Reproducible and Quantitative Model of Infection of Dermacentor variabilis with the Live Vaccine Strain of Francisella tularensis

    PubMed Central

    Coburn, Jenifer; Maier, Tamara; Casey, Monika; Padmore, Lavinia; Sato, Hiromi

    2014-01-01

    Pathogen life cycles in mammalian hosts have been studied extensively, but studies with arthropod vectors represent considerable challenges. In part this is due to the difficulty of delivering a reproducible dose of bacteria to follow arthropod-associated replication. We have established reproducible techniques to introduce known numbers of Francisella tularensis strain LVS from mice into Dermacentor variabilis nymphs. Using this model infection system, we performed dose-response infection experiments and followed bacterial replication through the molt to adults and at later time points. During development to adults, bacteria replicate to high numbers and can be found associated with the gut tissues, salivary glands, and hemolymph of adult ticks. Further, we can transmit a mutant of LVS (LVS ΔpurMCD) that cannot replicate in macrophages in vitro or in mice to nymphs. Our data show that the LVS ΔpurMCD mutant cannot be transstadially transmitted from nymphs to adult ticks. We then show that a plasmid-complemented strain of this mutant is recoverable in adult ticks and necessary for bacterial replication during the molt. In a mixed-infection assay (ΔpurMCD mutant versus ΔpurMCD complement), 98% of the recovered bacteria retained the plasmid marker. These data suggest that the ΔpurMCD mutation cannot be rescued by the presence a complemented strain in a mixed infection. Importantly, our infection model provides a platform to test specific mutants for their replication in ticks, perform competition studies, and use other genetic techniques to identify F. tularensis genes that are expressed or required in this unique environment. PMID:25362054

  2. Live attenuated vaccines for invasive Salmonella infections

    PubMed Central

    Tennant, Sharon M.; Levine, Myron M.

    2015-01-01

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

  3. Live attenuated vaccines for invasive Salmonella infections.

    PubMed

    Tennant, Sharon M; Levine, Myron M

    2015-06-19

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

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

    PubMed

    Kashirina, O S; Vasil'ev, Iu M

    2014-01-01

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

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

    PubMed Central

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

    1979-01-01

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

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

    PubMed

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

    2014-08-01

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

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

    PubMed Central

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

    2014-01-01

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

  8. Immune Responses to Circulating and Vaccine Viral Strains in HIV-Infected and Uninfected Children and Youth Who Received the 2013/2014 Quadrivalent Live-Attenuated Influenza Vaccine

    PubMed Central

    Weinberg, Adriana; Curtis, Donna; Ning, Mariangeli Freitas; Claypool, David Jeremy; Jalbert, Emilie; Patterson, Julie; Frank, Daniel N.; Ir, Diana; Armon, Carl

    2016-01-01

    The live-attenuated influenza vaccine (LAIV) has generally been more efficacious than the inactivated vaccine in children. However, LAIV is not recommended for HIV-infected children because of insufficient data. We compared cellular, humoral, and mucosal immune responses to the 2013–2014 LAIV quadrivalent (LAIV4) in HIV-infected and uninfected children 2–25 years of age (yoa). We analyzed the responses to the vaccine H1N1 (H1N1-09), to the circulating H1N1 (H1N1-14), which had significant mutations compared to H1N1-09 and to B Yamagata (BY), which had the highest effectiveness in 2013–2014. Forty-six HIV-infected and 56 uninfected participants with prior influenza immunization had blood and nasal swabs collected before and after LAIV4 for IFNγ T and IgG/IgA memory B-cell responses (ELISPOT), plasma antibodies [hemagglutination inhibition (HAI) and microneutralization (MN)], and mucosal IgA (ELISA). The HIV-infected participants had median CD4+ T cells = 645 cells/μL and plasma HIV RNA = 20 copies/mL. Eighty-four percent were on combination anti-retroviral therapy. Regardless of HIV status, significant increases in T-cell responses were observed against BY, but not against H1N1-09. H1N1-09 T-cell immunity was higher than H1N1-14 both before and after vaccination. LAIV4 significantly increased memory IgG B-cell immunity against H1N1-14 and BY in uninfected, but not in HIV-infected participants. Regardless of HIV status, H1N1-09 memory IgG B-cell immunity was higher than H1N1-14 and lower than BY. There were significant HAI titer increases after vaccination in all groups and against all viruses. However, H1N1-14 MN titers were significantly lower than H1N1-09 before and after vaccination overall and in HIV-uninfected vaccinees. Regardless of HIV status, LAIV4 increased nasal IgA concentrations against all viruses. The fold-increase in H1N1-09 IgA was lower than BY. Overall, participants <9 yoa had decreased BY-specific HAI and nasal IgA responses

  9. Hereditary hemochromatosis restores the virulence of plague vaccine strains.

    PubMed

    Quenee, Lauriane E; Hermanas, Timothy M; Ciletti, Nancy; Louvel, Helene; Miller, Nathan C; Elli, Derek; Blaylock, Bill; Mitchell, Anthony; Schroeder, Jay; Krausz, Thomas; Kanabrocki, Joseph; Schneewind, Olaf

    2012-10-01

    Nonpigmented Yersinia pestis (pgm) strains are defective in scavenging host iron and have been used in live-attenuated vaccines to combat plague epidemics. Recently, a Y. pestis pgm strain was isolated from a researcher with hereditary hemochromatosis who died from laboratory-acquired plague. We used hemojuvelin-knockout (Hjv(-/-)) mice to examine whether iron-storage disease restores the virulence defects of nonpigmented Y. pestis. Unlike wild-type mice, Hjv(-/-) mice developed lethal plague when challenged with Y. pestis pgm strains. Immunization of Hjv(-/-) mice with a subunit vaccine that blocks Y. pestis type III secretion generated protection against plague. Thus, individuals with hereditary hemochromatosis may be protected with subunit vaccines but should not be exposed to live-attenuated plague vaccines.

  10. Hereditary Hemochromatosis Restores the Virulence of Plague Vaccine Strains

    PubMed Central

    Quenee, Lauriane E.; Hermanas, Timothy M.; Ciletti, Nancy; Louvel, Helene; Miller, Nathan C.; Elli, Derek; Blaylock, Bill; Mitchell, Anthony; Schroeder, Jay; Krausz, Thomas; Kanabrocki, Joseph; Schneewind, Olaf

    2012-01-01

    Nonpigmented Yersinia pestis (pgm) strains are defective in scavenging host iron and have been used in live-attenuated vaccines to combat plague epidemics. Recently, a Y. pestis pgm strain was isolated from a researcher with hereditary hemochromatosis who died from laboratory-acquired plague. We used hemojuvelin-knockout (Hjv−/−) mice to examine whether iron-storage disease restores the virulence defects of nonpigmented Y. pestis. Unlike wild-type mice, Hjv−/− mice developed lethal plague when challenged with Y. pestis pgm strains. Immunization of Hjv−/− mice with a subunit vaccine that blocks Y. pestis type III secretion generated protection against plague. Thus, individuals with hereditary hemochromatosis may be protected with subunit vaccines but should not be exposed to live-attenuated plague vaccines. PMID:22896664

  11. A Salmonella Enteritidis hilAssrAfliG deletion mutant is a safe live vaccine strain that confers protection against colonization by Salmonella Enteritidis in broilers.

    PubMed

    De Cort, W; Geeraerts, S; Balan, V; Elroy, M; Haesebrouck, F; Ducatelle, R; Van Immerseel, F

    2013-10-17

    Consumption of contaminated poultry meat is an important cause of Salmonella infections in humans. Therefore, there is a need for control methods that protect broilers from day-of-hatch until slaughter age against infection with Salmonella. Colonization-inhibition, a concept in which a live Salmonella strain is orally administered to day-old chickens and protects against subsequent challenge, can potentially be used as control method. In this study, the safety and efficacy of a Salmonella Enteritidis ΔhilAssrAfliG strain as a colonization-inhibition strain for protection of broilers against Salmonella Enteritidis was evaluated. After administration of the Salmonella Enteritidis ΔhilAssrAfliG strain to day-old chickens, this strain could not be isolated from the gut, internal organs or faeces after 21 days of age. In addition, administration of this strain to one-day-old broiler chickens decreased faecal shedding and caecal and internal organ colonization of a Salmonella Enteritidis challenge strain administered one day later using a seeder bird model. To our knowledge, this is the first report of an attenuated Salmonella strain for which both the safety and efficacy has been shown in long-term experiments (until slaughter age) in broiler strain can potentially be used as a live colonization-inhibition strain for controlling Salmonella Enteritidis infections in broilers.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 bo...

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

    PubMed

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

    1962-09-01

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

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

    PubMed

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

    2017-02-01

    The efficacy of vaccination with Newcastle disease (ND) La Sota and R2B (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 log2 haemagglutination inhibition (HI) units, compared to a GMT of 6.0 log2 HI units following booster vaccination with R2B 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.

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

    MedlinePlus

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

  16. Identification of Strain-Specific Sequences That Distinguish a Mycoplasma gallisepticum Vaccine Strain from Field Isolates

    PubMed Central

    Ricketts, Camir; Pickler, Larissa; Maurer, John; Ayyampalayam, Saravanaraj; García, Maricarmen

    2016-01-01

    ABSTRACT Despite attempts to control avian mycoplasmosis through management, vaccination, and surveillance, Mycoplasma gallisepticum continues to cause significant morbidity, mortality, and economic losses in poultry production. Live attenuated vaccines are commonly used in the poultry industry to control avian mycoplasmosis; unfortunately, some vaccines may revert to virulence and vaccine strains are generally difficult to distinguish from natural field isolates. In order to identify genome differences among vaccine revertants, vaccine strains, and field isolates, whole-genome sequencing of the M. gallisepticum vaccine strain ts-11 and several “ts-11-like” strains isolated from commercial flocks was performed using Illumina and 454 pyrosequencing and the sequenced genomes compared to the M. gallisepticum Rlow reference genome. The collective contigs for each strain were annotated using the fully annotated Mycoplasma reference genome. The analysis revealed genetic differences among vlhA alleles, as well as among genes annotated as coding for a cell wall surface anchor protein (mg0377) and a hypothetical protein gene, mg0359, unique to M. gallisepticum ts-11 vaccine strain. PCR protocols were designed to target 5 sequences unique to the M. gallisepticum ts-11 strain: vlhA3.04a, vlhA3.04b, vlhA3.05, mg0377, and mg0359. All ts-11 isolates were positive for the five gene alleles tested by PCR; however, 5 to 36% of field isolates were also positive for at least one of the alleles tested. A combination of PCR tests for vlhA3.04a, vlhA3.05, and mg0359 was able to distinguish the M. gallisepticum ts-11 vaccine strain from field isolates. This method will further supplement current approaches to quickly distinguish M. gallisepticum vaccine strains from field isolates. PMID:27847370

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

    PubMed Central

    Wodarz, Dominik

    2008-01-01

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

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

    PubMed

    Stanfield, Brent; Kousoulas, Konstantin Gus

    2015-09-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

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

    PubMed

    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.

  5. Adaptation of the Endogenous Salmonella enterica Serovar Typhi clyA-Encoded Hemolysin for Antigen Export Enhances the Immunogenicity of Anthrax Protective Antigen Domain 4 Expressed by the Attenuated Live-Vector Vaccine Strain CVD 908-htrA

    PubMed Central

    Galen, James E.; Zhao, Licheng; Chinchilla, Magaly; Wang, Jin Yuan; Pasetti, Marcela F.; Green, Jeffrey; Levine, Myron M.

    2004-01-01

    Bacterial live-vector vaccines aim to deliver foreign antigens to the immune system and induce protective immune responses, and surface-expressed or secreted antigens are generally more immunogenic than cytoplasmic constructs. We hypothesize that an optimum expression system will use an endogenous export system to avoid the need for large amounts of heterologous DNA encoding additional proteins. Here we describe the cryptic chromosomally encoded 34-kDa cytolysin A hemolysin of Salmonella enterica serovar Typhi (ClyA) as a novel export system for the expression of heterologous antigens in the supernatant of attenuated Salmonella serovar Typhi live-vector vaccine strains. We constructed a genetic fusion of ClyA to the reporter green fluorescent protein and showed that in Salmonella serovar Typhi CVD 908-htrA, the fusion protein retains biological activity in both domains and is exported into the supernatant of an exponentially growing live vector in the absence of detectable bacterial lysis. The utility of ClyA for enhancing the immunogenicity of an otherwise problematic antigen was demonstrated by engineering ClyA fused to the domain 4 (D4) moiety of Bacillus anthracis protective antigen (PA). A total of 11 of 15 mice immunized intranasally with Salmonella serovar Typhi exporting the protein fusion manifested fourfold or greater rises in serum anti-PA immunoglobulin G, compared with only 1 of 16 mice immunized with the live vector expressing cytoplasmic D4 (P = 0.0002). In addition, the induction of PA-specific gamma interferon and interleukin 5 responses was observed in splenocytes. This technology offers exceptional versatility for enhancing the immunogenicity of bacterial live-vector vaccines. PMID:15557633

  6. Genogrouping of vaccine breakdown strains (VBS) of feline calicivirus in Japan.

    PubMed

    Ohe, K; Sakai, S; Takahasi, T; Sunaga, F; Murakami, M; Kiuchi, A; Fukuyama, M; Furuhata, K; Hara, M; Ishikawa, Y; Taneno, A

    2007-05-01

    Although prevention of feline calcivirus (FCV) infection by vaccination has been attempted, and isolation of FCV, development of the disease, and a few fatal cases in vaccinated cats have been reported. Fifteen FCV strains isolated from cats that had been vaccinated with commercially available FCV vaccines (F9, FCV-255, and FC-7) were genogrouped. Molecular analysis of viral genomes involved the construction of a phylogenetic tree of capsid genes using the NJ method. Cat anti-F9 serum and rabbit anti-FCV-255 serum were used for virus neutralization tests. Molecular phylogenetic analysis of the amino acid sequences of 15 virus isolates and those of the previously published and GenBank-deposited 9 global and 14 Japanese strains showed that 8 (53%) of the 15 virus isolates as well as the vaccine strains F9 and FCV-255 belonged to genogroup I (G(A)I), and 7 (47%) belonged to genogroup II (G(A)II). Of the 8 G(A)I strains, 2 were isolated from cats that had been vaccinated with an F9 strain live vaccine, 5 from cats vaccinated with an FCV-255-derived vaccine, and 1 from a cat vaccinated with an FC-7-derived vaccine. Of the 7 GAll strains, 5 were isolated from cats that had been vaccinated with the F9 strain live vaccine, 1 from a cat vaccinated with the FCV-255-derived vaccine, and 1 from a cat vaccinated with the FC-7-derived vaccine. These results indicate that more vaccine breakdown strains isolated from the cats vaccinated with the F9 strain-derived vaccine belong to G(A)II than to G(A)I, whereas more vaccine breakdown strains isolated from the cats vaccinated with the FCV-255 strain-derived vaccine belong to G(A)I than to G(A)II, and that when the FC-7 strain-derived vaccine is used, the vaccine breakdown strains belong almost equally to G(A)I and G(A)II. Thus, the genogroups of virus isolates varied with the vaccine strain used (p < 0.05). On the other hand, the neutralizing titres of feline anti-F9 serum and rabbit anti-FCV-255 serum against the 15 isolates were

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

    PubMed

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

    2009-03-30

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

  8. Antibody response and protection against challenge in mice vaccinated intraperitoneally with a live aroA O4-O9 hybrid Salmonella dublin strain.

    PubMed Central

    Lindberg, A A; Segall, T; Weintraub, A; Stocker, B A

    1993-01-01

    An auxotrophic Salmonella dublin (O9,12) strain, SL5631, with a deletion affecting gene aroA, was made into a partial diploid expressing the rfb (O-antigen-repeat-unit-specifying) gene cluster of Salmonella typhimurium (O4,12). By use of O4- and O9-specific antisera in indirect immunofluorescence assays, the resulting hybrid SL7103 was shown to express both the O4- and O9-antigen epitopes in the same bacterium. Qualitative and quantitative sugar analyses by gas-liquid chromatography on peralditol acetates of phenol-water-extracted lipopolysaccharides showed that the S. dublin and S. typhimurium repeating units (estimated on the basis of their tyvelose and abequose contents, respectively) were present in approximately equimolar amounts. The SL7103 hybrid auxotroph was avirulent when given intraperitoneally to NMRI mice in a dose of 10(8) CFU and elicited a protective immunity against intraperitoneal challenge with either virulent S. dublin (50% lethal dose of ca. 1.5 x 10(4) CFU versus < 1 x 10(1) CFU in nonimmunized mice) or virulent S. typhimurium (50% lethal dose of ca. 1 x 10(5) versus < 1 x 10(1) CFU in nonimmunized mice). Compared with the protection elicited in homologous systems (S. dublin SL5631 against S. dublin and S. typhimurium SL1479 against S. typhimurium), the protective efficacy of the hybrid was reduced approximately 70-fold against S. dublin challenge and 100-fold against S. typhimurium challenge. Vaccination with S. typhimurium SL1479 conferred no protection against S. dublin challenge, and vaccination with S. dublin SL5631 conferred no protection against S. typhimurium challenge. The protection elicited by the hybrid strain SL7103 is supposed to be mainly a consequence of serum antibodies directed against the immunodominant O4 and O9 epitopes. PMID:7681041

  9. Reassortant rotaviruses as potential live rotavirus vaccine candidates.

    PubMed Central

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

    1985-01-01

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

  10. Attenuated Shigella flexneri 2a ΔguaBA Strain CVD 1204 Expressing Enterotoxigenic Escherichia coli (ETEC) CS2 and CS3 Fimbriae as a Live Mucosal Vaccine against Shigella and ETEC Infection

    PubMed Central

    Altboum, Zeev; Barry, Eileen M.; Losonsky, Genevieve; Galen, James E.; Levine, Myron M.

    2001-01-01

    To construct a prototype hybrid vaccine against Shigella and enterotoxigenic Escherichia coli (ETEC), the genes encoding the production of ETEC CS2 and CS3 fimbriae were isolated and expressed in attenuated Shigella flexneri 2a guaBA strain CVD 1204. The CS2 cotA to -D genes, isolated from ETEC strain C91F, and the CS3 cstA to -H genes, subcloned from plasmid pCS100, were cloned into ∼15-copy-number-stabilized pGA1 behind the osmotically regulated ompC promoter, resulting in high expression of both fimbriae. Under nonselective in vitro growth conditions, pGA1-CS2 and pGA1-CS3 were stable in CVD 1204, exhibiting a plasmid loss of only approximately 1% per duplication. Expression of CS2 and CS3 reduced the invasiveness of Shigella for HeLa cells and slowed the intracellular growth rate. Guinea pigs immunized intranasally with CVD 1204(pGA1-CS2) or CVD 1204(pGA1-CS3), or with a mixture of these strains, developed secretory immunoglobulin A (IgA) in tears and serum IgG antibodies against Shigella lipopolysaccharide, CS2, and CS3 antigens. Moreover, the animals were protected against keratoconjunctivitis following conjunctival challenge with virulent S. flexneri 2a strain 2457T. Animals immunized with Shigella expressing CS2 or CS3 developed serum antibodies that agglutinated Shigella as well as an ETEC strain bearing the homologous fimbriae, whereas animals immunized with combined CVD 1204(pGA1-CS2) and CVD 1204(pGA1-CS3) developed antibodies that agglutinated all three test strains. These observations support the feasibility of a multivalent vaccine against shigellosis and ETEC diarrhea consisting of multiple Shigella live vectors expressing relevant ETEC antigens. PMID:11292735

  11. Genetic characterization of measles vaccine strains.

    PubMed

    Bankamp, Bettina; Takeda, Makoto; Zhang, Yan; Xu, Wenbo; Rota, Paul A

    2011-07-01

    The complete genomic sequences of 9 measles vaccine strains were compared with the sequence of the Edmonston wild-type virus. AIK-C, Moraten, Rubeovax, Schwarz, and Zagreb are vaccine strains of the Edmonston lineage, whereas CAM-70, Changchun-47, Leningrad-4 and Shanghai-191 were derived from 4 different wild-type isolates. Nucleotide substitutions were found in the noncoding regions of the genomes as well as in all coding regions, leading to deduced amino acid substitutions in all 8 viral proteins. Although the precise mechanisms involved in the attenuation of individual measles vaccines remain to be elucidated, in vitro assays of viral protein functions and recombinant viruses with defined genetic modifications have been used to characterize the differences between vaccine and wild-type strains. Although almost every protein contributes to an attenuated phenotype, substitutions affecting host cell tropism, virus assembly, and the ability to inhibit cellular antiviral defense mechanisms play an especially important role in attenuation.

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    1988-07-02

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

  16. Development of Streptococcus pneumoniae Vaccines Using Live Vectors

    PubMed Central

    Wang, Shifeng; Curtiss, Roy

    2014-01-01

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

  17. Live attenuated vaccines: Historical successes and current challenges

    SciTech Connect

    Minor, Philip D.

    2015-05-15

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

  18. A gE-negative BHV1 vaccine virus strain cannot perpetuate in cattle populations.

    PubMed

    Mars, M H; de Jong, M C; van Oirschot, J T

    2000-04-14

    Three identical transmission experiments were successively performed to quantitatively evaluate the possible transmission of a gE-negative bovine herpesvirus 1 (BHV1) vaccine strain among cattle. After intranasal inoculation, the vaccine virus was excreted in high titers in nasal fluids. However, the vaccine virus was transmitted to only one sentinel in one experiment, and not to any of the 10 sentinel cattle in the other two experiments. Based on these observations, it can be concluded that the expected number of cases per vaccine-inoculated animal, i.e. the transmission ratio R(0) of the vaccine strain, is significantly below 1. The R(0) was estimated to be 0.14. After intramuscular inoculation, shedding of vaccine virus was not detected. Therefore, we concluded that it is highly unlikely that this live gE-negative BHV1 vaccine strain will perpetuate in the cattle population.

  19. Permissive growth of human adenovirus type 4 vaccine strain-based vector in porcine cell lines.

    PubMed

    Gao, Dong-sheng; Li, Xiao-jing; Wan, Wen-yan; Li, Hong-jie; Wang, Xiao-xue; Yang, Xia; Li, Yong-tao; Chang, Hong-tao; Chen, Lu; Wang, Chuan-qing; Zhao, Jun

    2016-02-01

    In recent years, there has been considerable interest in using adenoviruses as live vectors to develop recombinant vaccines. Previous studies have demonstrated the safety and effectiveness of HIV/SIV and influenza vaccine candidates based on human adenovirus type 4 (Ad4) replication-competent vectors in rhesus macaque and human model. To explore the possibility of human Ad4 vaccine strain used as a vector in developing porcine vaccines, the growth properties of replication-competent human Ad4 vaccine strain recombinant encoding EGFP in different porcine cell lines were investigated. All tested cell lines are permissive for Ad4 vaccine strain vector with varied replication efficiency. Thus, human Ad4 based vectors would be promising supplement to adenovirus vectors as a delivery vehicle for recombinant vaccines in swine industry.

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

    PubMed

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

    2016-03-29

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

  1. Live bacterial vaccine vectors: An overview

    PubMed Central

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

    2014-01-01

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

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

    PubMed

    Gendon, Iu Z

    2004-01-01

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

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

    PubMed Central

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

    2013-01-01

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

  4. Reproductive, productivity, and mortality outcomes in late-gestation gilts and their litters following simulation of inadvertent exposure to a modified-live vaccine strain of porcine reproductive and respiratory syndrome (PRRS) virus.

    PubMed

    Schelkopf, Adam; Nerem, Joel; Cowles, Bobby; Amodie, Deb; Swalla, Richard; Dee, Scott

    2014-08-06

    The study evaluated the safety of a modified live-virus (MLV) porcine reproductive and respiratory syndrome (PRRS) vaccine in susceptible, pregnant gilts. To simulate inadvertent exposure secondary to postvaccination shedding of PRRS-MLV, seronegative gilts (n=51) were exposed by IM vaccination at 90 days of gestation. Vaccinated and nonvaccinated, seronegative control gilts (n=25) were maintained in separate facilities. The PRRS-MLV vaccine was given in a 2mL dose on day 0. On day 7 all vaccinated gilts were PRRSV-PCR-positive for PRRSV and had responded serologically as determined by an ELISA. All control gilts remained PRRSV-PCR- and ELISA-negative throughout the study. Abortions did not occur in gilts from either group. The difference between vaccinated and control gilts in average number of piglets per litter (12.43 and 12.16, respectively), number of live births per litter (11.21 and 11.54), and mean piglet birth weight (3.22 and 3.26 lbs) were not significantly different. Piglets in the control group had significantly greater average daily gain versus piglets from vaccinated gilts (0.52 vs. 0.46 lbs, P<0.0001). Preweaning mortality was significantly greater (P=0.0023) in piglets from the vaccinated gilts (19.7% vs. 10.9%). A single gilt accounted for 18.2% of stillbirths in the vaccinated group. Air samples were borderline PRRSV-PCR-positive for PRRSV on days 29 and 32, after more than 98% of gilts had farrowed. Results demonstrated that vaccination of pregnant gilts at the time of peak fetal susceptibility was non-abortigenic and that the PRRS-MLV agent did not significantly affect reproductive outcomes. Lower ADG in piglets from vaccinated gilts may be due to PRRS-MLV viremia following transplacental or post-farrowing exposure. Air sampling results indicated that environmental contamination with PRRS-MLV shed from vaccinated gilts was minimal.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2010-10-08

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

  7. Introduction of an update system for vaccine strains of veterinary influenza vaccines in Japan.

    PubMed

    Gamoh, Koichiro; Nakamura, Shigeyuki

    2015-03-01

    The basic countermeasures used to control highly pathogenic avian influenza (HPAI) are early detection procedures and the culling of affected chickens. However, if successive HPAI outbreaks occur, the vaccination may be an option for controlling HPAI. Therefore, avian influenza (AI) vaccines are stocked by the Japanese government. By contrast, equine influenza (EI) vaccine is an effective tool for preventing or controlling EI. Because antigenic drifts affect the efficacy of AI and EI vaccines, the vaccine strains should be updated rapidly. However, the development and registration of veterinary vaccines usually takes several years. In response to this issue, the Ministry of Agriculture, Forestry, and Fisheries (MAFF) established a system that allows AI and EI vaccine strains to be updated rapidly. National Veterinary Assay Laboratory, MAFF, established a vaccine strains selection committee for veterinary influenza vaccine. The main agendas involve determining whether the current vaccine strains need to be updated and selecting the most appropriate vaccine strains. The committee concluded that A/duck/Hokkaido/Vac-3/2007(H5N1) was added to the strains of stockpiled AI vaccines and that the EI vaccine strains did not need to be changed, but that the clade 2 viruses of the Florida sub-lineage strain, A/equine/Yokohama/aq13/2010(H3N8) was added to the EI vaccine strain.

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

    PubMed Central

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

    2012-01-01

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

  9. O-Antigen-Deficient Francisella tularensis Live Vaccine Strain Mutants Are Ingested via an Aberrant Form of Looping Phagocytosis and Show Altered Kinetics of Intracellular Trafficking in Human Macrophages

    PubMed Central

    Lee, Bai-Yu; Horwitz, Marcus A.

    2012-01-01

    We examined the uptake and intracellular trafficking of F. tularensis Live Vaccine Strain (LVS) and LVS with disruptions of wbtDEF and wbtI genes essential for synthesis of the O antigen of lipopolysaccharide. Unlike parental bacteria, O-antigen-deficient LVS is efficiently killed by serum with intact complement but not by serum lacking terminal complement components. Opsonization of O-antigen-deficient LVS in serum lacking terminal complement components allows efficient uptake of these live bacteria by macrophages. In the presence of complement, whereas parental F. tularensis LVS is internalized within spacious pseudopod loops, mutant LVS is internalized within tightly juxtaposed multiple onion-like layers of pseudopodia. Without complement, both parental and mutant LVSs are internalized within spacious pseudopod loops. Thus, molecules other than O antigen are important in triggering dramatic pseudopod extensions and uptake by spacious pseudopod loops. Following uptake, both parental and mutant LVSs enter compartments that show limited staining for the lysosomal membrane glycoprotein CD63 and little fusion with secondary lysosomes. Subsequently, both parental and mutant LVSs lose their CD63 staining. Whereas the majority of parental LVS escapes into the cytosol by 6 h after uptake, mutant LVS shows a marked lag but does escape by 1 day after uptake. Despite the altered kinetics of phagosome escape, both mutant and parental strains grow to high levels within human macrophages. Thus, the O antigen plays a role in the morphology of uptake in the presence of complement and the kinetics of intracellular growth but is not essential for escape, survival, altered membrane trafficking, or intramacrophage growth. PMID:22202123

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

    PubMed

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

    2011-06-01

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

  11. Research progress in live attenuated Brucella vaccine development.

    PubMed

    Wang, Zhen; Wu, Qingmin

    2013-01-01

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

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

    PubMed

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

    2011-05-01

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

  13. Genome Sequence of the Soviet/Russian Bacillus anthracis Vaccine Strain 55-VNIIVViM

    PubMed Central

    Kotorashvili, Adam

    2016-01-01

    Bacillus anthracis strain 55-VNIIVViM is a live-attenuated nonencapsulated Soviet/Russian veterinary anthrax vaccine strain. We report here the genome of 55-VNIIVViM and confirm its phylogenetic placement in the global population structure of B. anthracis. PMID:28007853

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

    PubMed

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

    2014-01-22

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

  15. Rescue of a vaccine strain of peste des petits ruminants virus: In vivo evaluation and comparison with standard vaccine

    PubMed Central

    Muniraju, Murali; Mahapatra, Mana; Buczkowski, Hubert; Batten, Carrie; Banyard, Ashley C.; Parida, Satya

    2015-01-01

    Across the developing world peste des petits ruminants virus places a huge disease burden on agriculture, primarily affecting the production of small ruminant. The disease is most effectively controlled by vaccinating sheep and goats with live attenuated vaccines that provide lifelong immunity. However, the current vaccines and serological tests are unable to enable Differentiation between naturally Infected and Vaccinated Animals (DIVA). This factor precludes meaningful assessment of vaccine coverage and epidemiological surveillance based on serology, in turn reducing the efficiency of control programmes. The availability of a recombinant PPRV vaccine with a proven functionality is a prerequisite for the development of novel vaccines that may enable the development of DIVA tools for PPRV diagnostics. In this study, we have established an efficient reverse genetics system for PPRV Nigeria 75/1 vaccine strain and, further rescued a version of PPRV Nigeria 75/1 vaccine strain that expresses eGFP as a novel transcription cassette and a version of PPRV Nigeria 75/1 vaccine strain with mutations in the haemagglutinin (H) gene to enable DIVA through disruption of binding to H by the C77 monoclonal antibody used in the competitive (c) H-ELISA. All three rescued viruses showed similar growth characteristics in vitro in comparison to parent vaccine strain and, following in vivo assessment the H mutant provided full protection in goats. Although the C77 monoclonal antibody used in the cH-ELISA was unable to bind to the mutated form of H in vitro, the mutation was not sufficient to enable DIVA in vivo. PMID:25444790

  16. Rescue of a vaccine strain of peste des petits ruminants virus: In vivo evaluation and comparison with standard vaccine.

    PubMed

    Muniraju, Murali; Mahapatra, Mana; Buczkowski, Hubert; Batten, Carrie; Banyard, Ashley C; Parida, Satya

    2015-01-09

    Across the developing world peste des petits ruminants virus places a huge disease burden on agriculture, primarily affecting the production of small ruminant. The disease is most effectively controlled by vaccinating sheep and goats with live attenuated vaccines that provide lifelong immunity. However, the current vaccines and serological tests are unable to enable Differentiation between naturally Infected and Vaccinated Animals (DIVA). This factor precludes meaningful assessment of vaccine coverage and epidemiological surveillance based on serology, in turn reducing the efficiency of control programmes. The availability of a recombinant PPRV vaccine with a proven functionality is a prerequisite for the development of novel vaccines that may enable the development of DIVA tools for PPRV diagnostics. In this study, we have established an efficient reverse genetics system for PPRV Nigeria 75/1 vaccine strain and, further rescued a version of PPRV Nigeria 75/1 vaccine strain that expresses eGFP as a novel transcription cassette and a version of PPRV Nigeria 75/1 vaccine strain with mutations in the haemagglutinin (H) gene to enable DIVA through disruption of binding to H by the C77 monoclonal antibody used in the competitive (c) H-ELISA. All three rescued viruses showed similar growth characteristics in vitro in comparison to parent vaccine strain and, following in vivo assessment the H mutant provided full protection in goats. Although the C77 monoclonal antibody used in the cH-ELISA was unable to bind to the mutated form of H in vitro, the mutation was not sufficient to enable DIVA in vivo.

  17. Live Attenuated and Inactivated Influenza Vaccines in Children

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2012-09-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed

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

    2015-07-09

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

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

    PubMed

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

    2006-09-01

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

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

    PubMed

    Yazbak, F Edward; Yazbak, Kathleen

    2002-09-01

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

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

    PubMed Central

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

    1974-01-01

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

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

    PubMed Central

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

    2006-01-01

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

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

    PubMed

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

    2015-08-07

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

  6. Salmonella Gallinarum field isolates from laying hens are related to the vaccine strain SG9R.

    PubMed

    Van Immerseel, F; Studholme, D J; Eeckhaut, V; Heyndrickx, M; Dewulf, J; Dewaele, I; Van Hoorebeke, S; Haesebrouck, F; Van Meirhaeghe, H; Ducatelle, R; Paszkiewicz, K; Titball, R W

    2013-10-09

    Salmonella enterica subspecies enterica serotype Gallinarum can cause severe systemic disease in chickens and a live Salmonella Gallinarum 9R vaccine (SG9R) has been used widely to control disease. Using whole-genome sequencing we found point mutations in the pyruvate dehydrogenase (aceE) and/or lipopolysaccharide 1,2-glucosyltransferase (rfaJ) genes that likely explain the attenuation of the SG9R vaccine strain. Molecular typing using Pulsed Field Gel Electrophoresis and Multiple-Locus Variable number of tandem repeat Analysis showed that strains isolated from different layer flocks in multiple countries and the SG9R vaccine strain were similar. The genome of one Salmonella Gallinarum field strain, isolated from a flock with a mortality peak and selected on the basis of identical PFGE and MLVA patterns with SG9R, was sequenced. We found 9 non-silent single-nucleotide differences distinguishing the field strain from the SG9R vaccine strain. Our data show that a Salmonella Gallinarum field strain isolated from laying hens is almost identical to the SG9R vaccine. Mutations in the aceE and rfaJ genes could explain the reversion to a more virulent phenotype. Our results highlight the importance of using well defined gene deletion mutants as vaccines.

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

    PubMed

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

    2016-11-02

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

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

    PubMed

    Terpstra, C; Kroese, A H

    1996-01-01

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

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

    PubMed

    Terpstra, C; Kroese, A H

    1996-04-01

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

  10. Evaluation of eight live attenuated vaccine candidates for protection against challenge with virulent Mycobacterium avium subspecies paratuberculosis in mice.

    PubMed

    Bannantine, John P; Everman, Jamie L; Rose, Sasha J; Babrak, Lmar; Katani, Robab; Barletta, Raúl G; Talaat, Adel M; Gröhn, Yrjö T; Chang, Yung-Fu; Kapur, Vivek; Bermudez, Luiz E

    2014-01-01

    Johne's disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), which results in serious economic losses worldwide in farmed livestock such as cattle, sheep, and goats. To control this disease, an effective vaccine with minimal adverse effects is needed. In order to identify a live vaccine for Johne's disease, we evaluated eight attenuated mutant strains of MAP using a C57BL/6 mouse model. The persistence of the vaccine candidates was measured at 6, 12, and 18 weeks post vaccination. Only strains 320, 321, and 329 colonized both the liver and spleens up until the 12-week time point. The remaining five mutants showed no survival in those tissues, indicating their complete attenuation in the mouse model. The candidate vaccine strains demonstrated different levels of protection based on colonization of the challenge strain in liver and spleen tissues at 12 and 18 weeks post vaccination. Based on total MAP burden in both tissues at both time points, strain 315 (MAP1566::Tn5370) was the most protective whereas strain 318 (intergenic Tn5367 insertion between MAP0282c and MAP0283c) had the most colonization. Mice vaccinated with an undiluted commercial vaccine preparation displayed the highest bacterial burden as well as enlarged spleens indicative of a strong infection. Selected vaccine strains that showed promise in the mouse model were moved forward into a goat challenge model. The results suggest that the mouse trial, as conducted, may have a relatively poor predictive value for protection in a ruminant host such as goats.

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

    PubMed

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

    2015-12-16

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

  12. Do vaccines save lives? Yes they do!

    PubMed

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

    2014-01-01

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

  13. Promises and pitfalls of live attenuated pneumococcal vaccines.

    PubMed

    Rosch, Jason W

    2014-01-01

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

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

    PubMed

    Popova, P Yu; Mikshis, N I

    2016-01-01

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

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2012-12-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

    Sudheesh, Ponnerassery S; Cain, Kenneth D

    2016-09-01

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

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

    PubMed

    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.

  1. Proteomic analysis of Mycoplasma gallisepticum vaccine strain F

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The persistence and displacement abilities of the Mycoplasma gallisepticum vaccine strain F (F-strain) are well documented. Understanding the mechanism(s) of colonization and persistence of F-strain will aid in the current intervention strategies to diagnose and control MG infections in poultry. In ...

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

    PubMed

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

    2011-06-30

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

  3. The haematological profile of female bronze turkeys (Meleagris gallopavo) vaccinated with various commercial strains of Newcastle disease.

    PubMed

    Schmidt, Elizabeth M d S; Santos, Ivan F C; Paulillo, António C; Martins, Gislaine R V; Denadai, Janine; Lapela, Ivan M

    2014-08-25

    The effects of vaccination on avian blood parameters are poorly understood. The present study was designed to evaluate whether different strains (Ulster 2C, B1, live LaSota and inactivated LaSota) of Newcastle disease vaccines had an effect on the haematological profile of female turkeys. Seventy-five female turkeys were allocated to treatment groups according to vaccination strain. All the birds, except those in the control group, were vaccinated at 32 weeks of age and revaccinated at 40 and 48 weeks of age. Blood samples were obtained for haematological analyses and serum samples for the haemagglutination inhibition test. Haemoglobin concentration was significantly lower (p < 0.05) in vaccinated female turkeys than in the control birds 28 days after vaccination. Monocytes were significantly higher (p < 0.05) in 44-week-old female turkeys vaccinated with inactivated LaSota strain compared with the other groups. Turkeys vaccinated with the B1 strain showed significantly higher (p < 0.05) total white blood cell counts compared with the other groups vaccinated with various commercial strains of the Newcastle disease virus. In conclusion, female turkeys showed significant differences in haemoglobin concentrations, monocytes and white blood cell counts when vaccinated against Newcastle disease.

  4. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

  5. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

  6. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

  7. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  8. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

  10. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  11. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  12. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

  13. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  14. Mycoplasma gallisepticum transmission: Comparison of commercial F-strain vaccine versus layer complex-derived field strains in a tunnel ventilated house

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two simultaneous trials were conducted using a commercially available, live, F strain Mycoplasma gallisepticum (FMG) vaccine [Trial 1] or two inocula of layer complex-derived MG strains (LCD-MG) [Trial 2]. In each of the two trials, four commercial turkeys were housed in each of two adjoining pens ...

  15. Safety of classical swine fever virus vaccine strain LOM in pregnant sows and their offspring.

    PubMed

    Lim, Seong-In; Song, Jae-Young; Kim, Jaejo; Hyun, Bang-Hun; Kim, Ha-Young; Cho, In-Soo; Kim, Byounghan; Woo, Gye-Hyeong; Lee, Jung-Bok; An, Dong-Jun

    2016-04-12

    The present study aimed to evaluate the safety of the classical swine fever virus (CSFV) vaccine strain LOM in pregnant sows. Pregnant sows with free CSFV antibody were inoculated with a commercial LOM vaccine during early pregnancy (day 38; n=3) or mid-pregnancy (days 49-59; n=11). In pregnant sows vaccinated during the early stages of gestation, abortion (day 109) was observed in one case, with two stillbirths and seven mummified fetuses. The viability of live-born piglets was 34.9% in sows vaccinated during mid-pregnancy compared with 81.8% in the control group. Post-mortem examination of the organs of the sows and piglets did not reveal any pathological lesions caused by CSFV; however, CSFV RNA was detected in the organs of several vaccinated sows and their litters. The LOM strain was transmitted from sows with free CSFV antibody to their fetus, but did not appear to induce immune tolerance in the offspring from vaccinated pregnant sows. Side effects were not observed in pregnant sows with antibody to the LOM strain: transmission from sow to their litters and stillbirth or mummified fetuses. The LOM strain may induce sterile immunity and provide rapid, long-lasting, and complete protection against CSFV; however, it should be contraindicated in pregnant sows due to potential adverse effects in pregnant sows with free CSFV antibody.

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

    PubMed

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

    2016-12-02

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

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

    DTIC Science & Technology

    2010-01-01

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

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

    PubMed

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

    2006-06-01

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

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

    PubMed Central

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

    2013-01-01

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

  20. Development of a highly immunogenic Newcastle disease virus chicken vaccine strain of duck origin.

    PubMed

    Kim, J Y; Kye, S J; Lee, H J; Gaikwad, S; Lee, H S; Jung, S C; Choi, K S

    2016-04-01

    Newcastle disease virus (NDV) strain NDRL0901 was developed as a live vaccine candidate for control of Newcastle disease. NDV isolate KR/duck/13/07 (DK1307) of duck origin was used as the selected vaccine strain. DK1307 was passaged 6 times in chickens. Then a single clone from the chicken-adapted virus (DK1307C) was finally selected, and the vaccine strain was named NDRL0901. DK1307C and the clone NDRL0901 viruses showed enhanced immunogenicity compared to the DK1307 virus. Principal component analysis based on fusion and hemagglutinin-neuraminidase genes revealed the codon usage pattern in the dataset is distinct separating duck viral sequences and avian sequences, and passage of the duck origin virus into the chicken host causes deviation in the codon usage pattern. The NDRL0901 virus was avirulent and did not acquire viral virulence even after 7 back passages in chickens. When day-old chicks were vaccinated with the NDRL0901 virus via spray, eye drops, and drinking water, the vaccinated birds showed no clinical signs and had significant protection efficacy (>80%) against very virulent NDV (Kr005 strain) infection regardless of the administration route employed. The results indicate that the NDRL0901 strain is safe in chickens and can offer protective immunity.

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

    PubMed Central

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

    2009-01-01

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

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

    PubMed Central

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

    2014-01-01

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

  3. Enhanced expression of HIV and SIV vaccine antigens in the structural gene region of live attenuated rubella viral vectors and their incorporation into virions.

    PubMed

    Virnik, Konstantin; Ni, Yisheng; Berkower, Ira

    2013-04-19

    Despite the urgent need for an HIV vaccine, its development has been hindered by virus variability, weak immunogenicity of conserved epitopes, and limited durability of the immune response. For other viruses, difficulties with immunogenicity were overcome by developing live attenuated vaccine strains. However, there is no reliable method of attenuation for HIV, and an attenuated strain would risk reversion to wild type. We have developed rubella viral vectors, based on the live attenuated vaccine strain RA27/3, which are capable of expressing important HIV and SIV vaccine antigens. The rubella vaccine strain has demonstrated safety, immunogenicity, and long lasting protection in millions of children. Rubella vectors combine the growth and immunogenicity of live rubella vaccine with the antigenicity of HIV or SIV inserts. This is the first report showing that live attenuated rubella vectors can stably express HIV and SIV vaccine antigens at an insertion site located within the structural gene region. Unlike the Not I site described previously, the new site accommodates a broader range of vaccine antigens without interfering with essential viral functions. In addition, antigens expressed at the structural site were controlled by the strong subgenomic promoter, resulting in higher levels and longer duration of antigen expression. The inserts were expressed as part of the structural polyprotein, processed to free antigen, and incorporated into rubella virions. The rubella vaccine strain readily infects rhesus macaques, and these animals will be the model of choice for testing vector growth in vivo and immunogenicity.

  4. Quantitative Determination of Lethal Toxin Proteins in Culture Supernatant of Human Live Anthrax Vaccine Bacillus anthracis A16R.

    PubMed

    Zai, Xiaodong; Zhang, Jun; Liu, Ju; Liu, Jie; Li, Liangliang; Yin, Ying; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-02-25

    Bacillus anthracis (B. anthracis) is the etiological agent of anthrax affecting both humans and animals. Anthrax toxin (AT) plays a major role in pathogenesis. It includes lethal toxin (LT) and edema toxin (ET), which are formed by the combination of protective antigen (PA) and lethal factor (LF) or edema factor (EF), respectively. The currently used human anthrax vaccine in China utilizes live-attenuated B. anthracis spores (A16R; pXO1+, pXO2-) that produce anthrax toxin but cannot produce the capsule. Anthrax toxins, especially LT, have key effects on both the immunogenicity and toxicity of human anthrax vaccines. Thus, determining quantities and biological activities of LT proteins expressed by the A16R strain is meaningful. Here, we explored LT expression patterns of the A16R strain in culture conditions using another vaccine strain Sterne as a control. We developed a sandwich ELISA and cytotoxicity-based method for quantitative detection of PA and LF. Expression and degradation of LT proteins were observed in culture supernatants over time. Additionally, LT proteins expressed by the A16R and Sterne strains were found to be monomeric and showed cytotoxic activity, which may be the main reason for side effects of live anthrax vaccines. Our work facilitates the characterization of anthrax vaccines components and establishment of a quality control standard for vaccine production which may ultimately help to ensure the efficacy and safety of the human anthrax vaccine A16R.

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

    DTIC Science & Technology

    1993-01-01

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

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

    PubMed

    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.

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

    PubMed

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

    2006-10-01

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

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

    PubMed

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

    2015-10-13

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

  9. Attenuated strains of Mycobacterium avium subspecies paratuberculosis as vaccine candidates against Johne's disease.

    PubMed

    Settles, Erik W; Kink, John A; Talaat, Adel

    2014-04-11

    Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) is the causative agent of Johne's disease in ruminants. Johne's disease has a severe economic impact on the dairy industry in the USA and worldwide. In an effort to combat this disease, we screened several transposon mutants that were attenuated in the murine model of paratuberculosis for the potential use as live attenuated vaccines. Using the murine model, two vaccine candidates (pgs1360, pgs3965 with mutations of fabG2_2 and umaA1, respectively) were at or below the limit of detection for tissue colonization suggesting their low level persistence and hence safety. Prior to challenge, both candidates induced a M. paratuberculosis-specific IFN-γ, an indication of eliciting cell-mediated immunity. Following challenge with a virulent strain of M. paratuberculosis, the two vaccine candidates significantly reduced bacterial colonization in organs with reduced histological scores compared to control animals. In addition, one of the vaccine candidates (pgs3965) also induced IL-17a, a cytokine associated with protective immunity in mycobacterial infection. Our analysis suggested that the pgs3965 vaccine candidate is a potential live-attenuated vaccine that could be tested further in ruminant models of paratuberculosis. The analysis also validated our screening strategy to identify effective vaccine candidates against intracellular pathogens.

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

    PubMed

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

    2017-03-08

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

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

    PubMed

    Mossad, Sherif B

    2003-09-01

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

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

    PubMed

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

    2016-04-22

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-03-01

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

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

    USGS Publications Warehouse

    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.

  16. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  17. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

  1. A pandemic influenza vaccine in India: from strain to sale within 12 months.

    PubMed

    Dhere, Rajeev; Yeolekar, Leena; Kulkarni, Prasad; Menon, Ravi; Vaidya, Vivek; Ganguly, Milan; Tyagi, Parikshit; Barde, Prajakt; Jadhav, Suresh

    2011-07-01

    In the event of a highly pathogenic influenza pandemic, the Indian subcontinent would need 1.2 billion doses of vaccine to immunize its entire population, double if two doses were required to assure immunity. Serum Institute of India Limited (SII) thus became one of six initial grantees of the World Health Organization (WHO) technology transfer initiative to create capacity in developing countries to manufacture H5N1 pandemic influenza vaccine. At the outbreak of the A(H1N1) 2009 influenza pandemic, experience gained from the H5N1 project was used to develop a live attenuated influenza vaccine (LAIV), since this was the only option for the level of surge capacity required for a large-scale immunization campaign in India. SII took <12 months to develop and market its LAIV intranasal vaccine from receipt of the seed strain from WHO. As of November 2010, over 2.5 million persons have been vaccinated with Nasovac(®) with no serious adverse reactions or vaccine failure after 3 months' post-marketing surveillance. The product has been submitted for prequalification by WHO for purchase by United Nations agencies. In parallel, SII also developed an inactivated influenza vaccine, and is currently looking to ensure the sustainability of its influenza vaccine manufacturing capacity.

  2. Protection Induced in Broiler Chickens following Drinking-Water Delivery of Live Infectious Laryngotracheitis Vaccines against Subsequent Challenge with Recombinant Field Virus.

    PubMed

    Korsa, Mesula G; Browning, Glenn F; Coppo, Mauricio J C; Legione, Alistair R; Gilkerson, James R; Noormohammadi, Amir H; Vaz, Paola K; Lee, Sang-Won; Devlin, Joanne M; Hartley, Carol A

    2015-01-01

    Infectious laryngotracheitis virus (ILTV) causes acute upper respiratory tract disease in chickens. Attenuated live ILTV vaccines are often used to help control disease, but these vaccines have well documented limitations, including retention of residual virulence, incomplete protection, transmission of vaccine virus to unvaccinated birds and reversion to high levels of virulence following bird-to-bird passage. Recently, two novel ILTV field strains (class 8 and 9 ILTV viruses) emerged in Australia due to natural recombination between two genotypically distinct commercial ILTV vaccines. These recombinant field strains became dominant field strains in important poultry producing areas. In Victoria, Australia, the recombinant class 9 virus largely displaced the previously predominant class 2 ILTV strain. The ability of ILTV vaccines to protect against challenge with the novel class 9 ILTV strain has not been studied. Here, the protection induced by direct (drinking-water) and indirect (contact) exposure to four different ILTV vaccines against challenge with class 9 ILTV in commercial broilers was studied. The vaccines significantly reduced, but did not prevent, challenge virus replication in vaccinated chickens. Only one vaccine significantly reduced the severity of tracheal pathology after direct drinking-water vaccination. The results indicate that the current vaccines can be used to help control class 9 ILTV, but also indicate that these vaccines have limitations that should be considered when designing and implementing disease control programs.

  3. Update of inactivated equine influenza vaccine strain in Japan

    PubMed Central

    GAMOH, Koichiro; NAKAMURA, Shigeyuki

    2017-01-01

    Japan established a vaccine selection system, in which a committee evaluates veterinary influenza vaccines to determine if the vaccine should be updated. In 2013, it was concluded that the present equine influenza vaccine strains did not have to be updated, but clade 2 (Fc2) viruses of the Florida sublineage should be included. We collected three Fc2 viruses as candidates and conducted comparative tests. Results indicated that A/equine/Carlow/2011 (H3N8) is not suitable, because of its unstable antigenic characteristics. A comparison between A/equine/Richmond/1/2007 (H3N8) (Richmond/07) and A/equine/Yokohama/aq13/2010 (H3N8) (Yokohama/10) in eggs showed that they shared equal growth properties. Immunogenicity test in mice showed that Yokohama/10 induced higher HI antibody titers than Richmond/07. Therefore, we concluded that Yokohama/10 was the most suitable strain. PMID:28163276

  4. Assessment of protective efficacy of live and killed vaccines based on a non-encapsulated mutant of Streptococcus suis serotype 2.

    PubMed

    Wisselink, Henk J; Stockhofe-Zurwieden, Norbert; Hilgers, Luuk A T; Smith, Hilde E

    2002-01-03

    The protective efficacy of a live and killed non-encapsulated isogenic mutant of Streptococcus suis serotype 2 was determined in pigs, and compared with the efficacy of the capsulated wild-type strain. SPF pigs were vaccinated twice intramuscularly at 4 and 7 weeks of age with a dose of 1 x 10(9) formalin-killed CFU of the wild-type (WT-BAC), formalin-killed non-encapsulated mutant (CM-BAC) or live non-encapsulated mutant (CM-LIVE) strain. After 2 weeks, vaccinated pigs and non-vaccinated controls were challenged intravenously with 1 x 10(7) CFU of the homologous, wild-type S. suis serotype 2 strain. Protection was evaluated by clinical, bacteriological, serological and post-mortem examinations. All pigs vaccinated with WT-BAC were completely protected against challenge with the homologous serotype. Pigs vaccinated with CM-BAC were partially protected. Although all pigs vaccinated with CM-BAC survived the challenge, four out of five pigs developed clinical signs of disease for several days. Compared to the WT-BAC and CM-BAC, the CM-LIVE vaccine was less protective. Two out of five pigs vaccinated with CM-LIVE died in the course of the experiment and all of them developed specific clinical signs of disease for several days. The protective efficacy of the vaccines could be associated with serum antibody titers. Antibody titers against cells of wild-type and non-encapsulated mutant strains as well as against muramidase-released proteins (MRP) were high in pigs vaccinated with WT-BAC and CM-BAC. Pigs vaccinated with CM-LIVE showed lower antibody titers. Antibody titers against purified capsular polysaccharides (CPS) of S. suis serotype 2 were only found in pigs vaccinated with WT-BAC. These findings indicate that CPS and other bacterial components of WT-BAC are probably essential for full protection against homologous challenge.

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

    PubMed

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

    2016-05-01

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

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

    PubMed

    Vesikari, T

    1993-01-01

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

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

    PubMed

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

    2016-01-12

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

  8. A candidate live inactivatable attenuated vaccine for AIDS.

    PubMed Central

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

    1996-01-01

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

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2012-07-20

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

  12. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  13. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

  14. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  17. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

  18. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

  19. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

  1. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

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

    PubMed

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

    2014-05-23

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

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

    PubMed

    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.

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

    PubMed

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

    2015-09-08

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

  5. Complete Genome Sequences of Bordetella pertussis Vaccine Reference Strains 134 and 10536

    PubMed Central

    Peng, Yanhui; Loparev, Vladimir; Batra, Dhwani; Burroughs, Mark; Johnson, Taccara; Juieng, Phalasy; Rowe, Lori; Tondella, M. Lucia; Williams, Margaret M.

    2016-01-01

    Vaccine formulations and vaccination programs against whooping cough (pertussis) vary worldwide. Here, we report the complete genome sequences of two divergent Bordetella pertussis reference strains used in the production of pertussis vaccines. PMID:27635001

  6. Effects of live and killed vaccines against Mycoplasma gallisepticum on the performance characteristics of commercial layer chickens.

    PubMed

    Jacob, R; Branton, S L; Evans, J D; Leigh, S A; Peebles, E D

    2014-06-01

    Different vaccine strains of Mycoplasma gallisepticum have been used on multiple-age commercial layer farms in an effort to protect birds against virulent field-strain infections. Use of the F-strain of M. gallisepticum (FMG), as an overlay vaccine during lay, may be necessary because of the lower level of protection afforded by M. gallisepticum vaccines of low virulence given before lay. Two replicate trials were conducted to investigate effects of live and killed M. gallisepticum vaccines administered individually and in combination before lay, in conjunction with an FMG vaccine overlay after peak egg production (EP), on the performance characteristics of commercial layers. The following treatments were utilized at 10 wk of age (woa): 1) control (no vaccinations); 2) ts11 strain M. gallisepticum (ts11MG) vaccine; 3) M. gallisepticum-Bacterin vaccine (MG-Bacterin); and 4) ts11MG and MG-Bacterin vaccines combination. At 45 woa, half of the birds were overlaid with an FMG vaccine. Hen mortality, BW, egg weight, percentage hen-day EP, egg blood spots, and egg meat spots were determined at various time periods between 18 and 52 woa. The data from each trial were pooled. Treatment did not affect performance in interval I (23 to 45 woa). However, during interval II (46 to 52 woa), the EP of control and MG-Bacterin-vaccinated birds that later received an FMG vaccine overlay was lower than that in the other treatment groups. Furthermore, treatment application reduced bird BW during interval II. Despite the effects on BW and EP, no differences were observed for egg blood or meat spots among the various treatments. It is suggested that the vaccination of commercial layers before lay with ts11MG, but not MG-Bacterin, may reduce the negative impacts of an FMG overlay vaccination given during lay. These results establish that the vaccination of pullets with ts11MG in combination with the vaccination of hens with an FMG overlay, for continual protection against field-strain M

  7. Infection and transmission of live recombinant Newcastle disease virus vaccines in Rock Pigeons, European House Sparrows, and Japanese Quail

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In China and Mexico, engineered recombinant Newcastle disease virus (rNDV) strains are used as live vaccines for the control of Newcastle disease and as vectors to express the avian influenza virus hemagglutinin (HA) gene to control avian influenza in poultry. In this study, non-target species wer...

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    2014-12-01

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

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

    PubMed

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

    2015-12-10

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

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

    PubMed

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

    2009-10-01

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

  14. B-cell responses after intranasal vaccination with the novel attenuated Bordetella pertussis vaccine strain BPZE1 in a randomized phase I clinical trial.

    PubMed

    Jahnmatz, Maja; Amu, Sylvie; Ljungman, Margaretha; Wehlin, Lena; Chiodi, Francesca; Mielcarek, Nathalie; Locht, Camille; Thorstensson, Rigmor

    2014-06-05

    Despite high vaccination coverage, pertussis is still a global concern in infant morbidity and mortality, and improved pertussis vaccines are needed. A live attenuated Bordetella pertussis strain, named BPZE1, was designed as an intranasal vaccine candidate and has recently been tested in man in a phase I clinical trial. Here, we report the evaluation of the B-cell responses after vaccination with BPZE1. Forty-eight healthy males with no previous pertussis-vaccination were randomized into one of three dose-escalating groups or into a placebo group. Plasma blast- and memory B-cell responses were evaluated by ELISpot against three different pertussis antigens: pertussis toxin, filamentous haemagglutinin and pertactin. Seven out of the 36 subjects who had received the vaccine were colonized by BPZE1, and significant increases in the memory B-cell response were detected against all three tested antigens in the culture-positive subjects between days 0 and 28 post-vaccination. The culture-positive subjects also mounted a significant increase in the filamentous haemagglutinin-specific plasma blast response between days 7 and 14 post-vaccination. No response could be detected in the culture-negatives or in the placebo group post-vaccination. These data show that BPZE1 is immunogenic in humans and is therefore a promising candidate for a novel pertussis vaccine. This trial is registered at ClinicalTrials.gov (NCT01188512).

  15. A natural vaccine candidate strain against cholera.

    PubMed

    Liu, Y Q; Qi, G M; Wang, S X; Yu, Y M; Duan, G C; Zhang, L J; Gao, S Y

    1995-12-01

    E1 Tor Vibrio cholerae (EVC) strains may be classified into two kinds-epidemigenic (EEVC) strains and non-epidemigenic (NEEVC) strains-based on a phage-biotyping system. A large number of EEVC strains have been screened for toxigenic and putative colonization attributes. One such naturally occurring strains (designated IEM101) has been found which is devoid of genes encoding cholera toxin (CT), accessory cholera enterotoxin (ACE), zonula occludens toxin (ZOT), but possesses RS1 sequences and toxin-coregulated pilus A gene (icpA) although icpA is poorly expressed. It expresses type B pili but does not possess type C pili. It is an E1 Tor Ogawa strain and does not cause fluid accumulation in rabbit ilcal loop tests. Active immunization of rabbits with strain IEM101 elicited good protection against challenge with virulent strains of V. cholerae O1. Oral administration caused no side effects in 15 human volunteers, colonized the gut for four to ten days and elicited good immune responses.

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    1997-01-01

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

  18. Live Attenuated Mutants of Francisella tularensis Protect Rabbits against Aerosol Challenge with a Virulent Type A Strain

    PubMed Central

    Smith, Le'Kneitah P.; Cole, Kelly Stefano; Santiago, Araceli E.; Mann, Barbara J.; Barry, Eileen M.

    2014-01-01

    Francisella tularensis, a Gram-negative bacterium, is the causative agent of tularemia. No licensed vaccine is currently available for protection against tularemia, although an attenuated strain, dubbed the live vaccine strain (LVS), is given to at-risk laboratory personnel as an investigational new drug (IND). In an effort to develop a vaccine that offers better protection, recombinant attenuated derivatives of a virulent type A strain, SCHU S4, were evaluated in New Zealand White (NZW) rabbits. Rabbits vaccinated via scarification with the three attenuated derivatives (SCHU S4 ΔguaBA, ΔaroD, and ΔfipB strains) or with LVS developed a mild fever, but no weight loss was detected. Twenty-one days after vaccination, all vaccinated rabbits were seropositive for IgG to F. tularensis lipopolysaccharide (LPS). Thirty days after vaccination, all rabbits were challenged with aerosolized SCHU S4 at doses ranging from 50 to 500 50% lethal doses (LD50). All rabbits developed fevers and weight loss after challenge, but the severity was greater for mock-vaccinated rabbits. The ΔguaBA and ΔaroD SCHU S4 derivatives provided partial protection against death (27 to 36%) and a prolonged time to death compared to results for the mock-vaccinated group. In contrast, LVS and the ΔfipB strain both prolonged the time to death, but there were no survivors from the challenge. This is the first demonstration of vaccine efficacy against aerosol challenge with virulent type A F. tularensis in a species other than a rodent since the original work with LVS in the 1960s. The ΔguaBA and ΔaroD SCHU S4 derivatives warrant further evaluation and consideration as potential vaccines for tularemia and for identification of immunological correlates of protection. PMID:24614653

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. Safety and immunogenicity of a live attenuated mumps vaccine

    PubMed Central

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

    2014-01-01

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

  1. A Novel Live Vector Group A Streptococcal emm Type 9 Vaccine Delivered Intranasally Protects Mice against Challenge Infection with emm Type 9 Group A Streptococci

    PubMed Central

    García, Patricia; Geoffroy, Enrique A.; Aguirre, Daniel B.; González, Samantha A.; Sarno, Victoria A.; Dale, James B.; Salazar-Echegarai, Francisco J.; Vera, Andrea; Bueno, Susan M.; Kalergis, Alexis M.

    2014-01-01

    The availability of a protective vaccine against Streptococcus pyogenes (group A Streptococcus [GAS]) is a priority for public health worldwide. Here, we have generated six live vaccine strains, each engineered to express an N-terminal M protein peptide from one of six of the most prevalent emm types of GAS (M1, M2, M4, M9, M12, and M28). The vaccine strains are based on a food-grade Lactococcus lactis strain and do not bear any antibiotic resistance. Mice immunized with the vaccine strain expressing the M9 peptide (termed here the L. lactis M9 strain) showed high titers of serum antibodies when delivered intranasally. Mice immunized with the L. lactis M9 strain were protected against infection after intranasal challenge with type 9 streptococci. Several parameters of disease, such as weight loss, body temperature, colony counts in mouth washes, and lung histology, were significantly improved in immunized mice compared to naive control mice. Our results indicate that intranasal delivery of the L. lactis M9 strain live bacterial vaccine induced GAS-specific IgG titers, prevented pharyngeal colonization of GAS, and protected mice from disease upon challenge. The design of this vaccine prototype may provide a lower cost alternative to vaccines comprised of purified recombinant proteins. PMID:25056362

  2. A novel live vector group A streptococcal emm type 9 vaccine delivered intranasally protects mice against challenge infection with emm type 9 group A streptococci.

    PubMed

    Wozniak, Aniela; García, Patricia; Geoffroy, Enrique A; Aguirre, Daniel B; González, Samantha A; Sarno, Victoria A; Dale, James B; Salazar-Echegarai, Francisco J; Vera, Andrea; Bueno, Susan M; Kalergis, Alexis M

    2014-09-01

    The availability of a protective vaccine against Streptococcus pyogenes (group A Streptococcus [GAS]) is a priority for public health worldwide. Here, we have generated six live vaccine strains, each engineered to express an N-terminal M protein peptide from one of six of the most prevalent emm types of GAS (M1, M2, M4, M9, M12, and M28). The vaccine strains are based on a food-grade Lactococcus lactis strain and do not bear any antibiotic resistance. Mice immunized with the vaccine strain expressing the M9 peptide (termed here the L. lactis M9 strain) showed high titers of serum antibodies when delivered intranasally. Mice immunized with the L. lactis M9 strain were protected against infection after intranasal challenge with type 9 streptococci. Several parameters of disease, such as weight loss, body temperature, colony counts in mouth washes, and lung histology, were significantly improved in immunized mice compared to naive control mice. Our results indicate that intranasal delivery of the L. lactis M9 strain live bacterial vaccine induced GAS-specific IgG titers, prevented pharyngeal colonization of GAS, and protected mice from disease upon challenge. The design of this vaccine prototype may provide a lower cost alternative to vaccines comprised of purified recombinant proteins.

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

    PubMed

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

    2006-07-01

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

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

    PubMed Central

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

    2006-01-01

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

  5. Seasonal Effectiveness of Live Attenuated and Inactivated Influenza Vaccine

    PubMed Central

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

    2016-01-01

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

  6. 76 FR 3075 - Availability of an Environmental Assessment for Field Testing Feline Leukemia Vaccine, Live...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

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

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

    PubMed Central

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

    1998-01-01

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

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

    PubMed

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

    2010-04-21

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

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

    PubMed

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

    2012-03-01

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

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

    PubMed

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

    2009-08-01

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

  11. Protection by novel vaccine candidates, Mycobacterium tuberculosis ΔmosR and ΔechA7, against challenge with a Mycobacterium tuberculosis Beijing strain.

    PubMed

    Marcus, Sarah A; Steinberg, Howard; Talaat, Adel M

    2015-10-13

    Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB), infects over two billion people, claiming around 1.5 million lives annually. The only vaccine approved for clinical use against this disease is the Bacillus Calmette-Guérin (BCG) vaccine. Unfortunately, BCG has limited efficacy against the adult, pulmonary form of tuberculosis. This vaccine was developed from M. bovis with antigen expression and host specificity that differ from M. tuberculosis. To address these problems, we have designed two novel, live attenuated vaccine (LAV) candidates on an M. tuberculosis background: ΔmosR and ΔechA7. These targeted genes are important to M. tuberculosis pathogenicity during infection. To examine the efficacy of these strains, C57BL/6 mice were vaccinated subcutaneously with either LAV, BCG, or PBS. Both LAV strains persisted up to 16 weeks in the spleens or lungs of vaccinated mice, while eliciting minimal pathology prior to challenge. Following challenge with a selected, high virulence M. tuberculosis Beijing strain, protection was notably greater for both groups of LAV vaccinated animals as compared to BCG at both 30 and 60 days post-challenge. Additionally, vaccination with either ΔmosR or ΔechA7 elicited an immune response similar to BCG. Although these strains require further development to meet safety standards, this first evidence of protection by these two new, live attenuated vaccine candidates shows promise.

  12. Differential Immune Responses and Protective Effects in Avirulent Mycobacterial Strains Vaccinated BALB/c Mice.

    PubMed

    Liu, Laicheng; Fu, Ruiling; Yuan, Xuefeng; Shi, Chunwei; Wang, Shuling; Lu, Xianyu; Ma, Zhao; Zhang, Xiaoming; Qin, Weiyan; Fan, Xionglin

    2015-07-01

    Screening live mycobacterial vaccine candidates is the important strategy to develop new vaccines against adult tuberculosis (TB). In this study, the immunogenicity and protective efficacy of several avirulent mycobacterial strains including Mycobacterium smegmatis, M. vaccae, M. terrae, M. phlei, M. trivial, and M. tuberculosis H37Ra were compared with M. bovis BCG in BALB/c mice. Our results demonstrated that differential immune responses were induced in different mycobacterial species vaccinated mice. As BCG-vaccinated mice did, M. terrae immunization resulted in Th1-type responses in the lung, as well as splenocytes secreting IFN-γ against a highly conserved mycobacterial antigen Ag85A. M. smegmatis also induced the same splenocytes secreting IFN-γ as BCG and M. terrae did. In addition, M. terrae and M. smegmatis-immunized mice predominantly increased expression of IL-10 and TGF-β in the lung. Most importantly, mice vaccinated with H37Ra and M. vaccae could provide the same protection in the lung against virulent M. tuberculosis challenge as BCG. The result may have important implications in developing adult TB vaccine.

  13. Detection of cold-adapted vaccine-strain influenza virus using two commercial assays.

    PubMed

    Adam, E N; Morley, P S; Chmielewski, K E; Carman, J; Gonzales, G

    2002-07-01

    Because of the contagious nature of influenza virus it is necessary to identify infected individuals after the virus is introduced into a population. The aim of this study was to characterise influenza virus detection with commercially available assays after intranasal vaccinating horses with cold-adapted influenza virus. Seven horses were vaccinated and placed with 3 unvaccinated horses. Nasal secretion samples were evaluated using 2 antigen detection assays. All 10 horses were positive in the Flu OIA assay during the study period, but only one horse was positive on one sample using the Directigen Flu A assay. Horses were most likely to be positive during the first 3 days following vaccination, and several horses were intermittently positive for several days after this. Obtaining positive test results from nonvaccinated, incontact horses suggests they became infected with vaccine-strain virus that was shed by vaccinated horses. These results are important for the correct interpretation of influenza antigen detection tests in situations when this modified-live intranasal vaccine has been used.

  14. Characterization of Francisella tularensis Schu S4 defined mutants as live-attenuated vaccine candidates.

    PubMed

    Santiago, Araceli E; Mann, Barbara J; Qin, Aiping; Cunningham, Aimee L; Cole, Leah E; Grassel, Christen; Vogel, Stefanie N; Levine, Myron M; Barry, Eileen M

    2015-08-01

    Francisella tularensis (Ft), the etiological agent of tularemia and a Tier 1 select agent, has been previously weaponized and remains a high priority for vaccine development. Ft tularensis (type A) and Ft holarctica (type B) cause most human disease. We selected six attenuating genes from the live vaccine strain (LVS; type B), F. novicida and other intracellular bacteria: FTT0507, FTT0584, FTT0742, FTT1019c (guaA), FTT1043 (mip) and FTT1317c (guaB) and created unmarked deletion mutants of each in the highly human virulent Ft strain Schu S4 (Type A) background. FTT0507, FTT0584, FTT0742 and FTT1043 Schu S4 mutants were not attenuated for virulence in vitro or in vivo. In contrast, Schu S4 gua mutants were unable to replicate in murine macrophages and were attenuated in vivo, with an i.n. LD50 > 10(5) CFU in C57BL/6 mice. However, the gua mutants failed to protect mice against lethal challenge with WT Schu S4, despite demonstrating partial protection in rabbits in a previous study. These results contrast with the highly protective capacity of LVS gua mutants against a lethal LVS challenge in mice, and underscore differences between these strains and the animal models in which they are evaluated, and therefore have important implications for vaccine development.

  15. Attenuated PfSPZ Vaccine induces strain-transcending T cells and durable protection against heterologous controlled human malaria infection.

    PubMed

    Lyke, Kirsten E; Ishizuka, Andrew S; Berry, Andrea A; Chakravarty, Sumana; DeZure, Adam; Enama, Mary E; James, Eric R; Billingsley, Peter F; Gunasekera, Anusha; Manoj, Anita; Li, Minglin; Ruben, Adam J; Li, Tao; Eappen, Abraham G; Stafford, Richard E; Kc, Natasha; Murshedkar, Tooba; Mendoza, Floreliz H; Gordon, Ingelise J; Zephir, Kathryn L; Holman, LaSonji A; Plummer, Sarah H; Hendel, Cynthia S; Novik, Laura; Costner, Pamela J M; Saunders, Jamie G; Berkowitz, Nina M; Flynn, Barbara J; Nason, Martha C; Garver, Lindsay S; Laurens, Matthew B; Plowe, Christopher V; Richie, Thomas L; Graham, Barney S; Roederer, Mario; Sim, B Kim Lee; Ledgerwood, Julie E; Hoffman, Stephen L; Seder, Robert A

    2017-02-21

    A live-attenuated malaria vaccine, Plasmodium falciparum sporozoite vaccine (PfSPZ Vaccine), confers sterile protection against controlled human malaria infection (CHMI) with Plasmodium falciparum (Pf) parasites homologous to the vaccine strain up to 14 mo after final vaccination. No injectable malaria vaccine has demonstrated long-term protection against CHMI using Pf parasites heterologous to the vaccine strain. Here, we conducted an open-label trial with PfSPZ Vaccine at a dose of 9.0 × 10(5) PfSPZ administered i.v. three times at 8-wk intervals to 15 malaria-naive adults. After CHMI with homologous Pf parasites 19 wk after final immunization, nine (64%) of 14 (95% CI, 35-87%) vaccinated volunteers remained without parasitemia compared with none of six nonvaccinated controls (P = 0.012). Of the nine nonparasitemic subjects, six underwent repeat CHMI with heterologous Pf7G8 parasites 33 wk after final immunization. Five (83%) of six (95% CI, 36-99%) remained without parasitemia compared with none of six nonvaccinated controls. PfSPZ-specific T-cell and antibody responses were detected in all vaccine recipients. Cytokine production by T cells from vaccinated subjects after in vitro stimulation with homologous (NF54) or heterologous (7G8) PfSPZ were highly correlated. Interestingly, PfSPZ-specific T-cell responses in the blood peaked after the first immunization and were not enhanced by subsequent immunizations. Collectively, these data suggest durable protection against homologous and heterologous Pf parasites can be achieved with PfSPZ Vaccine. Ongoing studies will determine whether protective efficacy can be enhanced by additional alterations in the vaccine dose and number of immunizations.

  16. Genetic characteristics of Neisseria meningitidis serogroup B strains carried by adolescents living in Milan, Italy

    PubMed Central

    Esposito, Susanna; Zampiero, Alberto; Terranova, Leonardo; Montinaro, Valentina; Scala, Alessia; Ansuini, Valentina; Principi, Nicola

    2013-01-01

    Before a protein vaccine is introduced into a country, it is essential to evaluate its potential impact and estimate its benefits and costs. The aim of this study was to determine the genetic characteristics of Neisseria meningitidis B (NmB) in the pharyngeal secretions of 1375 healthy adolescents aged 13–19 y living in Milan, Italy, in September 2012, and the possible protection offered by the two currently available NmB protein vaccines. Ninety-one subjects were Nm carriers (6.6%), 29 (31.9%) of whom carried the NmB capsular gene. The 29 identified strains belonged to eight clonal complexes (CCs), the majority of which were in the ST-41/44/Lin.3 CC (n = 11; 37.9%). All of the identified strains harboured ƒHbp alleles representing a total of 15 sub-variants: the gene for NHBA protein was found in all but three of the studied strains (10.3%) with 13 identified sub-variants. There were 15 porA sub-types, seven of which were identified in just one CC. The findings of this study seem to suggest that both of the protein vaccines proposed for the prevention of invasive disease due to NmB (the 4-protein and the 2-protein products) have a composition that can evoke a theoretically effective antibody response against the meningococcal strains currently carried by adolescents living in Northern Italy. The genetic characteristics of NmB strains can be easily evaluated by means of molecular methods, the results of which can provide an albeit approximate estimate of the degree of protection theoretically provided by the available vaccines, and the possible future need to change their composition. PMID:23880917

  17. Protective immunity induced by immunization with a live, cultured Anaplasma marginale strain

    PubMed Central

    Hammac, G. Kenitra; Ku, Pei-Shin; Galletti, Maria F.; Noh, Susan M.; Scoles, Glen A.; Palmer, Guy H.; Brayton, Kelly A.

    2014-01-01

    Despite significant economic losses resulting from infection with Anaplasma marginale, a tick-transmitted rickettsial pathogen of cattle, available vaccines provide, at best, only partial protection against clinical disease. The green-fluorescent protein expressing mutant of the A. marginale St. Maries strain is a live, marked vaccine candidate (AmStM-GFP1). To test whether AmStM-GFP is safe and provides clinical protection, a group of calves was vaccinated, and clinical parameters, including percent parasitized erythrocytes (PPE), packed cell volume (PCV) and days required to reach peak bacteremia, were measured following inoculation and following tick challenge with wild type St Maries strain (AmStM). These clinical parameters were compared to those obtained during infection with the A. marginale subsp. centrale vaccine strain (A. centrale) or wild type AmStM. AmStM-GFP resulted in similar clinical parameters to A. centrale, but had a lower maximum PPE, smaller drop in PCV and took longer to reach peak bacteremia than wild type AmStM. AmStM-GFP provided clinical protection, yielding a stable PCV and low bacteremia following challenge, whereas A. centrale only afforded partial clinical protection. PMID:23664994

  18. The haematological profile of female bronze turkeys (Meleagris gallopavo) vaccinated with various commercial strains of Newcastle disease.

    PubMed

    Schmidt, Elizabeth M D S; Santos, Ivan F C; Paulillo, António C; Martins, Gislaine R V; Denadai, Janine; Lapela, Ivan M

    2014-08-25

    The effects of vaccination on avian blood parameters are poorly understood. The present study was designed to evaluate whether different strains (Ulster 2C, B1, live LaSota and inactivated LaSota) of Newcastle disease vaccines had an effect on the haematological profile of female turkeys. Seventy-five female turkeys were allocated to treatment groups according to vaccination strain. All the birds, except those in the control group, were vaccinated at 32 weeks of age and revaccinated at 40 and 48 weeks of age. Blood samples were obtained for haematological analyses and serum samples for the haemagglutination inhibition test. Haemoglobin concentration was significantly lower (p < 0.05) in vaccinated female turkeys than in the control birds 28 days after vaccination. Monocytes were significantly higher (p < 0.05) in 44-week-old female turkeys vaccinated with inactivated LaSota strain compared with the other groups. Turkeys vaccinated with the B1 strain showed significantly higher (p < 0.05) total white blood cell counts compared with the other groups vaccinated with various commercial strains of the Newcastle disease virus. In conclusion, female turkeys showed significant differences in haemoglobin concentrations, monocytes and white blood cell counts when vaccinated against Newcastle disease.

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

    PubMed

    Ebrahimi, Mohammad; Nejad, Ramin Bagheri; Alamian, Saeed; Mokhberalsafa, Ladan; Abedini, Fatemeh; Ghaderi, Rainak; Jalali, Hamid Reza

    2012-01-01

    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 × 10(6), 10(6), 5 × 10(5)). 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 × 10(6) Rev. 1 organisms than in those which received 10(6) or 5 × 10(5) 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 10(6) or 5 × 10(5) live cells could be safely used to induce protection in Iranian fat-tailed sheep at various stages of pregnancy.

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

    PubMed Central

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

    2007-01-01

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

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

    PubMed

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

    2002-10-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. Burkholderia mallei CLH001 Attenuated Vaccine Strain Is Immunogenic and Protects against Acute Respiratory Glanders

    PubMed Central

    Hatcher, Christopher L.; Mott, Tiffany M.; Muruato, Laura A.; Sbrana, Elena

    2016-01-01

    Burkholderia mallei is the causative agent of glanders, an incapacitating disease with high mortality rates in respiratory cases. Its endemicity and ineffective treatment options emphasize its public health threat and highlight the need for a vaccine. Live attenuated vaccines are considered the most viable vaccine strategy for Burkholderia, but single-gene-deletion mutants have not provided complete protection. In this study, we constructed the select-agent-excluded B. mallei ΔtonB Δhcp1 (CLH001) vaccine strain and investigated its ability to protect against acute respiratory glanders. Here we show that CLH001 is attenuated, safe, and effective at protecting against lethal B. mallei challenge. Intranasal administration of CLH001 to BALB/c and NOD SCID gamma (NSG) mice resulted in complete survival without detectable colonization or abnormal organ histopathology. Additionally, BALB/c mice intranasally immunized with CLH001 in a prime/boost regimen were fully protected against lethal challenge with the B. mallei lux (CSM001) wild-type strain. PMID:27271739

  4. Safety and efficacy of a metabolic drift live attenuated Salmonella Gallinarum vaccine against fowl typhoid.

    PubMed

    Shehata, Awad Ali; Sultan, Hesham; Hafez, Hafez M; Krüger, Monika

    2013-03-01

    Fowl typhoid (FT), a systemic disease that results in septicemia in poultry, is caused by Salmonella enterica serovar Gallinarum biovar Gallinarum (SG). Mortality and morbidity rates from FT can reach up to 80%. Attenuated live Salmonella vaccine candidates have received considerable attention because they confer solid immunity, and they can produce systemic and mucosal immunity in the gut when administered orally. In the present study, five metabolic drift (MD) mutants with a single-(designated SG-Rif1, SG-Sm6) or double-attenuating marker (designated SG-Rif1-Sm4, SG-Sm6-Rif10, and SG-Rif1-Sm10) were isolated. The relative colony sizes to wild-type strain after 24 hr at 37 C incubation were 50%, 40%, 30%, 30%, and 20%, respectively. The probability of a back mutation can almost be excluded because the reduced colony sizes were stable after at least 50 passages on culture media. The safety and immunogenicity were evaluated in susceptible 1-day-old commercial layer chickens. After oral administration of 10(8) colony-forming units (CFU), all developed MD mutants proved to be safe and did not cause death of any infected birds during 15 days postvaccination, whereas chickens receiving 10(6) CFU SG wild-type strain showed a high mortality rate (40%). Vaccination of commercial layer chicks with SG-Rif1, SG-Sm6, SG-Rif1-Sm4, and SG-Sm6-Rif10 MD mutants could protect chickens against challenge by homologous wild-type strain; however, SG-Rif1-Sm10 could not protect against challenge, indicating hyperattenuation. In conclusion, vaccination with SG MD mutant vaccine appears to be safe and offers protection against FT in chickens.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2015-04-01

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

  7. A dual-strain feline calicivirus vaccine stimulates broader cross-neutralization antibodies than a single-strain vaccine and lessens clinical signs in vaccinated cats when challenged with a homologous feline calicivirus strain associated with virulent systemic disease.

    PubMed

    Huang, Chengjin; Hess, Jennifer; Gill, Michael; Hustead, David

    2010-02-01

    Feline calicivirus (FCV) causes an array of clinical disease in cats. Traditionally this disease has been associated with respiratory disease, limping, or chronic stomatitis. Within the last 10 years, virulent systemic feline calicivirus (VS-FCV) has been recognized which causes additional clinical signs and has a higher fatality rate. A dual-strain FCV vaccine containing a strain of FCV associated with traditional respiratory disease and a VS-FCV strain stimulates serum cross-neutralization antibodies when tested against field strains from Europe and VS-FCV strains from USA. Following challenge with a homologous VS-FCV strain, vaccinated cats had significantly reduced clinical signs.

  8. A Wide Extent of Inter-Strain Diversity in Virulent and Vaccine Strains of Alphaherpesviruses

    PubMed Central

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

    2011-01-01

    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

  9. Safety and immunogenicity of a live-attenuated auxotrophic candidate vaccine against the intracellular pathogen Rhodococcus equi.

    PubMed

    Lopez, A M; Townsend, H G G; Allen, A L; Hondalus, M K

    2008-02-13

    Rhodococcus equi causes serious pneumonia in neonatal foals and is an opportunistic pathogen of people with compromised cellular immunity. No effective vaccine against R. equi disease in foals is available. We tested the safety and immunogenicity of a live, fully attenuated riboflavin auxotrophic candidate vaccine strain of R. equi (R. equi rib-). We demonstrated that R. equi rib- is immunogenic and capable of inducing IFN-gamma responses in immunocompetent BALB/c mice, yet it is safe even in an immunocompromised SCID mouse infection model. Moreover, it protects immunocompetent mice against virulent R. equi challenge. In foals, R. equi rib- was likewise safe and stimulated serum R. equi-specific immune responses. A preliminary immunization strategy did not afford protection against virulent R. equi challenge and therefore, optimization of the vaccine formulation and or vaccination protocol will be necessary.

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

    PubMed

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

    2008-02-01

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

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

    PubMed

    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.

  12. Comparison of the protective efficacies of the live vaccine RIT 4025 and an inactivated vaccine against a natural heterologous A/Victoria/3/75 infection.

    PubMed

    Delem, A; Van Rensburg, W; Flaskett, I

    1979-10-01

    A clinical trial was initiated in South Africa before the winter season of 1976. The study involved 253 volunteers divided into three groups of vaccinees and one control group. Two groups of vaccinees were inoculated with either one or two doses at 2 weeks' interval (10(7.2) EID 50/dose) of the RIT 4025 live recombinant strain [A/Scotland/840/74 (H3N2) serotype] and one group received one injection of an inactivated vaccine [A/Port Chalmers/1/73 (H3N2), 360 i.u., A/Scotland/840/74 (H3N2), 300 i.u. and B/Hong Kong/8/73, 300 i.u./dose]. The serum antihaemagglutinin antibody responses against the heterologous A/Victoria/3/75 strain as measured by the single radial haemolysis test were satisfactory and not statistically different in all groups of vaccinees. On the other hand, the antineuraminidase antibody response was better in the group receiving the killed vaccine. At the end of the influenza season, A/Victoria/3/75 infections were confirmed serologically. Only 12% of the infections were symptomatic. The infection rate was significantly reduced in the live vaccine groups, whereas in the killed vaccine group the percentage of infection was lower but not significantly different from that in the placebo group.

  13. A new approach to an influenza live vaccine: modification of the cleavage site of hemagglutinin.

    PubMed

    Stech, J; Garn, H; Wegmann, M; Wagner, R; Klenk, H-D

    2005-06-01

    A promising approach to reduce the impact of influenza is the use of an attenuated, live virus as a vaccine. Using reverse genetics, we generated a mutant of strain A/WSN/33 with a modified cleavage site within its hemagglutinin, which depends on proteolytic activation by elastase. Unlike the wild-type, which requires trypsin, this mutant is strictly dependent on elastase. Both viruses grow equally well in cell culture. In contrast to the lethal wild-type virus, the mutant is entirely attenuated in mice. At a dose of 10(5) plaque-forming units, it induced complete protection against lethal challenge. This approach allows the conversion of any epidemic strain into a genetically homologous attenuated virus.

  14. [Vaccination against mouse pox].

    PubMed

    Mahnel, H

    1985-01-01

    Attenuated MVA-strain of vaccinia virus has been efficient in the control of enzootic mousepox and in prophylactic vaccination. The virus has been used as a live vaccine for prophylactic and emergency vaccinations as well as for sanitation of populations. More than 100 000 vaccinations were carried out safely. Even after suspension of the obligatory vaccination of humans against smallpox the MVA-vaccine can be employed without risk and danger.

  15. Fulminant encephalitis associated with a vaccine strain of rubella virus.

    PubMed

    Gualberto, Felipe Augusto Souza; de Oliveira, Maria Isabel; Alves, Venancio A F; Kanamura, Cristina T; Rosemberg, Sérgio; Sato, Helena Keico; Arantes, Benedito A F; Curti, Suely Pires; Figueiredo, Cristina Adelaide

    2013-12-01

    Involvement of the central nervous system is common in measles, but rare in rubella. However, rubella virus (RV) can cause a variety of central nervous system syndromes, including meningitis, encephalitis, Guillain-Barré syndrome and sub acute sclerosing panencephalitis. We report the occurrence of one fatal case of the encephalitis associated with measles-rubella (MR) vaccine during an immunization campaign in São Paulo, Brazil. A 31 year-old-man, previously in good health, was admitted at emergency room, with confusion, agitation, inability to stand and hold his head up. Ten days prior to admission, he was vaccinated with combined MR vaccine (Serum Institute of India) and three days later he developed 'flu-like' illness with fever, myalgia and headache. Results of clinical and laboratory exams were consistent with a pattern of viral encephalitis. During hospitalization, his condition deteriorated rapidly with tetraplegia and progression to coma. On the 3rd day of hospitalization he died. Histopathology confirmed encephalitis and immunohistochemistry was positive for RV on brain tissue. RV was also detected by qPCR and virus isolation in cerebrospinal fluid, brain and other clinical samples. The sequence obtained from the isolated virus was identical to that of the RA 27/3 vaccine strain.

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

    PubMed

    Yamshchikov, Vladimir

    2015-10-01

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

  17. A bivalent typhoid live vector vaccine expressing both chromosome- and plasmid-encoded Yersinia pestis antigens fully protects against murine lethal pulmonary plague infection.

    PubMed

    Galen, James E; Wang, Jin Yuan; Carrasco, Jose A; Lloyd, Scott A; Mellado-Sanchez, Gabriela; Diaz-McNair, Jovita; Franco, Olga; Buskirk, Amanda D; Nataro, James P; Pasetti, Marcela F

    2015-01-01

    Live attenuated bacteria hold great promise as multivalent mucosal vaccines against a variety of pathogens. A major challenge of this approach has been the successful delivery of sufficient amounts of vaccine antigens to adequately prime the immune system without overattenuating the live vaccine. Here we used a live attenuated Salmonella enterica serovar Typhi strain to create a bivalent mucosal plague vaccine that produces both the protective F1 capsular antigen of Yersinia pestis and the LcrV protein required for secretion of virulence effector proteins. To reduce the metabolic burden associated with the coexpression of F1 and LcrV within the live vector, we balanced expression of both antigens by combining plasmid-based expression of F1 with chromosomal expression of LcrV from three independent loci. The immunogenicity and protective efficacy of this novel vaccine were assessed in mice by using a heterologous prime-boost immunization strategy and compared to those of a conventional strain in which F1 and LcrV were expressed from a single low-copy-number plasmid. The serum antibody responses to lipopolysaccharide (LPS) induced by the optimized bivalent vaccine were indistinguishable from those elicited by the parent strain, suggesting an adequate immunogenic capacity maintained through preservation of bacterial fitness; in contrast, LPS titers were 10-fold lower in mice immunized with the conventional vaccine strain. Importantly, mice receiving the optimized bivalent vaccine were fully protected against lethal pulmonary challenge. These results demonstrate the feasibility of distributing foreign antigen expression across both chromosomal and plasmid locations within a single vaccine organism for induction of protective immunity.

  18. A Bivalent Typhoid Live Vector Vaccine Expressing both Chromosome- and Plasmid-Encoded Yersinia pestis Antigens Fully Protects against Murine Lethal Pulmonary Plague Infection

    PubMed Central

    Wang, Jin Yuan; Carrasco, Jose A.; Lloyd, Scott A.; Mellado-Sanchez, Gabriela; Diaz-McNair, Jovita; Franco, Olga; Buskirk, Amanda D.; Nataro, James P.; Pasetti, Marcela F.

    2014-01-01

    Live attenuated bacteria hold great promise as multivalent mucosal vaccines against a variety of pathogens. A major challenge of this approach has been the successful delivery of sufficient amounts of vaccine antigens to adequately prime the immune system without overattenuating the live vaccine. Here we used a live attenuated Salmonella enterica serovar Typhi strain to create a bivalent mucosal plague vaccine that produces both the protective F1 capsular antigen of Yersinia pestis and the LcrV protein required for secretion of virulence effector proteins. To reduce the metabolic burden associated with the coexpression of F1 and LcrV within the live vector, we balanced expression of both antigens by combining plasmid-based expression of F1 with chromosomal expression of LcrV from three independent loci. The immunogenicity and protective efficacy of this novel vaccine were assessed in mice by using a heterologous prime-boost immunization strategy and compared to those of a conventional strain in which F1 and LcrV were expressed from a single low-copy-number plasmid. The serum antibody responses to lipopolysaccharide (LPS) induced by the optimized bivalent vaccine were indistinguishable from those elicited by the parent strain, suggesting an adequate immunogenic capacity maintained through preservation of bacterial fitness; in contrast, LPS titers were 10-fold lower in mice immunized with the conventional vaccine strain. Importantly, mice receiving the optimized bivalent vaccine were fully protected against lethal pulmonary challenge. These results demonstrate the feasibility of distributing foreign antigen expression across both chromosomal and plasmid locations within a single vaccine organism for induction of protective immunity. PMID:25332120

  19. Refined live attenuated Salmonella enterica serovar Typhimurium and Enteritidis vaccines mediate homologous and heterologous serogroup protection in mice.

    PubMed

    Tennant, Sharon M; Schmidlein, Patrick; Simon, Raphael; Pasetti, Marcela F; Galen, James E; Levine, Myron M

    2015-12-01

    Invasive nontyphoidal Salmonella (NTS) infections constitute a major health problem among infants and toddlers in sub-Saharan Africa; these infections also occur in infants and the elderly in developed countries. We genetically engineered a Salmonella enterica serovar Typhimurium strain of multilocus sequence type 313, the predominant genotype circulating in sub-Saharan Africa. We evaluated the capacities of S. Typhimurium and Salmonella enterica serovar Enteritidis ΔguaBA ΔclpX live oral vaccines to protect mice against a highly lethal challenge dose of the homologous serovar and determined protection against other group B and D serovars circulating in sub-Saharan Africa. The vaccines S. Typhimurium CVD 1931 and S. Enteritidis CVD 1944 were immunogenic and protected BALB/c mice against 10,000 50% lethal doses (LD50) of S. Typhimurium or S. Enteritidis, respectively. S. Typhimurium CVD 1931 protected mice against the group B serovar Salmonella enterica serovar Stanleyville (91% vaccine efficacy), and S. Enteritidis CVD 1944 protected mice against the group D serovar Salmonella enterica serovar Dublin (85% vaccine efficacy). High rates of survival were observed when mice were infected 12 weeks postimmunization, indicating that the vaccines elicited long-lived protective immunity. Whereas CVD 1931 did not protect against S. Enteritidis R11, CVD 1944 did mediate protection against S. Typhimurium D65 (81% efficacy). These findings suggest that a bivalent (S. Typhimurium and S. Enteritidis) vaccine would provide broad protection against the majority of invasive NTS infections in sub-Saharan Africa.

  20. Refined Live Attenuated Salmonella enterica Serovar Typhimurium and Enteritidis Vaccines Mediate Homologous and Heterologous Serogroup Protection in Mice

    PubMed Central

    Schmidlein, Patrick; Simon, Raphael; Pasetti, Marcela F.; Galen, James E.; Levine, Myron M.

    2015-01-01

    Invasive nontyphoidal Salmonella (NTS) infections constitute a major health problem among infants and toddlers in sub-Saharan Africa; these infections also occur in infants and the elderly in developed countries. We genetically engineered a Salmonella enterica serovar Typhimurium strain of multilocus sequence type 313, the predominant genotype circulating in sub-Saharan Africa. We evaluated the capacities of S. Typhimurium and Salmonella enterica serovar Enteritidis ΔguaBA ΔclpX live oral vaccines to protect mice against a highly lethal challenge dose of the homologous serovar and determined protection against other group B and D serovars circulating in sub-Saharan Africa. The vaccines S. Typhimurium CVD 1931 and S. Enteritidis CVD 1944 were immunogenic and protected BALB/c mice against 10,000 50% lethal doses (LD50) of S. Typhimurium or S. Enteritidis, respectively. S. Typhimurium CVD 1931 protected mice against the group B serovar Salmonella enterica serovar Stanleyville (91% vaccine efficacy), and S. Enteritidis CVD 1944 protected mice against the group D serovar Salmonella enterica serovar Dublin (85% vaccine efficacy). High rates of survival were observed when mice were infected 12 weeks postimmunization, indicating that the vaccines elicited long-lived protective immunity. Whereas CVD 1931 did not protect against S. Enteritidis R11, CVD 1944 did mediate protection against S. Typhimurium D65 (81% efficacy). These findings suggest that a bivalent (S. Typhimurium and S. Enteritidis) vaccine would provide broad protection against the majority of invasive NTS infections in sub-Saharan Africa. PMID:26351285

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

    PubMed Central

    2004-01-01

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

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

    PubMed

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

    2016-05-01

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

  3. A gE-negative bovine herpesvirus 1 vaccine strain is not re-excreted nor transmitted in an experimental cattle population after corticosteroid treatments.

    PubMed

    Mars, M H; de Jong, M C; van Oirschot, J T

    2000-04-03

    To study possible reactivation and to quantify subsequent transmission of a live gE-negative bovine herpesvirus 1 (BHV1) vaccine strain in cattle populations, four experiments were performed. Two groups of cattle were each tested twice for the possibility of reactivation. Inoculation with a gE-negative BHV1 vaccine was done either intramuscularly or intranasally and treatment with corticosteroids in an attempt to reactivate vaccine virus, was done after 6 or 11 weeks, and again after 6 months. To quantify transmission of vaccine virus following possible reactivation, each cattle was housed together with one susceptible contact-cattle. Contact-infections were monitored using virus shedding and antibody responses. After corticosteroid treatments, re-excretion of virus was never detected in cattle that had been inoculated with the gE-negative BHV1 vaccine strain. Contact cattle did not shed gE-negative BHV1, nor mounted any antibody response against BHV1. In contrast, positive control cattle, inoculated intranasally with wild-type BHV1, re-excreted virus in high titers in nasal fluids and transmitted the virus to contact cattle. Based on these results, the transmission ratio R(0) of the vaccine strain was zero. We concluded that it is highly unlikely that the live gE-negative BHV1 vaccine strain will be re-excreted after possible reactivation, and consequently, it is even less likely that reactivated vaccine virus will spread in the cattle population.

  4. DIVERGENCE, NOT DIVERSITY OF AN ATTENUATED EQUINE LENTIVIRUS VACCINE STRAIN CORRELATES WITH PROTECTION FROM DISEASE

    PubMed Central

    Craigo, Jodi K.; Barnes, Shannon; Cook, Sheila J.; Issel, Charles J.; Montelaro, Ronald C.

    2010-01-01

    We recently reported an attenuated EIAV vaccine study that directly examined the effect of lentiviral envelope sequence variation on vaccine efficacy. The study [1] demonstrated for the first time the failure of an ancestral vaccine to protect and revealed a significant, inverse, linear relationship between envelope divergence and protection from disease. In the current study we examine in detail the evolution of the attenuated vaccine strain utilized in this previous study. We demonstrate here that the attenuated strain progressively evolved during the six-month pre-challenge period and that the observed protection from disease was significantly associated with divergence from the original vaccine strain. PMID:20955830

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

    PubMed Central

    Subramanian, Rahul; Graham, Andrea L.; Grenfell, Bryan T.; Arinaminpathy, Nimalan

    2016-01-01

    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 vaccination

  6. Comparative analysis of the immunologic response induced by the Sterne 34F2 live spore Bacillus anthracis vaccine in a ruminant model.

    PubMed

    Ndumnego, Okechukwu C; Köhler, Susanne M; Crafford, Jannie; van Heerden, Henriette; Beyer, Wolfgang

    2016-10-01

    The Sterne 34F2 live spore vaccine (SLSV) developed in 1937 is the most widely used veterinary vaccine against anthrax. However, literature on the immunogenicity of this vaccine in a target ruminant host is scarce. In this study, we evaluated the humoral response to the Bacillus anthracis protective antigen (rPA), a recombinant bacillus collagen-like protein of anthracis (rBclA), formaldehyde inactivated spores (FIS) prepared from strain 34F2 and a vegetative antigen formulation prepared from a capsule and toxin deficient strain (CDC 1014) in Boer goats. The toxin neutralizing ability of induced antibodies was evaluated using an in vitro toxin neutralization assay. The protection afforded by the vaccine was also assessed in vaccinates. Anti-rPA, anti-FIS and lethal toxin neutralizing titres were superior after booster vaccinations, compared to single vaccinations. Qualitative analysis of humoral responses to rPA, rBclA and FIS antigens revealed a preponderance of anti-FIS IgG titres following either single or double vaccinations with the SLSV. Antibodies against FIS and rPA both increased by 350 and 300-fold following revaccinations respectively. There was no response to rBclA following vaccinations with the SLSV. Toxin neutralizing titres increased by 80-fold after single vaccination and 700-fold following a double vaccination. Lethal challenge studies in naïve goats indicated a minimum infective dose of 36 B. anthracis spores. Single and double vaccination with the SLSV protected 4/5 and 3/3 of goats challenged with>800 spores respectively. An early booster vaccination following the first immunization is suggested in order to achieve a robust immunity. Results from this study indicate that this crucial second vaccination can be administered as early as 3 months after the initial vaccination.

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

    PubMed

    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.

  8. A Web-Based Platform for Designing Vaccines against Existing and Emerging Strains of Mycobacterium tuberculosis

    PubMed Central

    Dhanda, Sandeep Kumar; Vir, Pooja; Singla, Deepak; Gupta, Sudheer; Kumar, Shailesh

    2016-01-01

    Development of an effective vaccine against drug-resistant Mycobacterium tuberculosis (Mtb) is crucial for saving millions of premature deaths every year due to tuberculosis. This paper describes a web portal developed for assisting researchers in designing vaccines against emerging Mtb strains using traditional and modern approaches. Firstly, we annotated 59 genomes of Mycobacterium species to understand similarity/dissimilarity between tuberculoid, non-tuberculoid and vaccine strains at genome level. Secondly, antigen-based vaccine candidates have been predicted in each Mtb strain. Thirdly, epitopes-based vaccine candidates were predicted/discovered in above antigen-based vaccine candidates that can stimulate all arms of immune system. Finally, a database of predicted vaccine candidates at epitopes as well at antigen level has been developed for above strains. In order to design vaccine against a newly sequenced genome of Mtb strain, server integrates three modules for identification of strain-, antigen-, epitope-specific vaccine candidates. We observed that 103522 unique peptides (9mers) had the potential to induce an antibody response and/or promiscuous binder to MHC alleles and/or have the capability to stimulate T lymphocytes. In summary, this web-portal will be useful for researchers working on designing vaccines against Mtb including drug-resistant strains. Availability: The database is available freely at http://crdd.osdd.net/raghava/mtbveb/. PMID:27096425

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

    PubMed

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

    2015-03-15

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

  10. Detection of Mycoplasma mycoides subsp. mycoides SC in bronchoalveolar lavage fluids of cows based on a TaqMan real-time PCR discriminating wild type strains from an lppQ− mutant vaccine strain used for DIVA-strategies

    PubMed Central

    Vilei, Edy M.; Frey, Joachim

    2010-01-01

    Contagious bovine pleuropneumonia (CBPP) is the most serious cattle disease in Africa, caused by Mycoplasma mycoides subsp. mycoides small-colony type (SC). CBPP control strategies currently rely on vaccination with a vaccine based on live attenuated strains of the organism. Recently, an lppQ− mutant of the existing vaccine strain T1/44 has been developed (Janis et al., 2008). This T1lppQ− mutant strain is devoid of lipoprotein LppQ, a potential virulence attribute of M. mycoides subsp. mycoides SC. It is designated as a potential live DIVA (Differentiating Infected from Vaccinated Animals) vaccine strain allowing both serological and etiological differentiation. The present paper reports on the validation of a control strategy for CBPP in cattle, whereby a TaqMan real-time PCR based on the lppQ gene has been developed for the direct detection of M. mycoides subsp. mycoides SC in ex vivo bronchoalveolar lavage fluids of cows and for the discrimination of wild type strains from the lppQ− mutant vaccine strain. PMID:20381545

  11. A Brucella melitensis M5-90 wboA deletion strain is attenuated and enhances vaccine efficacy.

    PubMed

    Li, Zhi-Qiang; Shi, Jing-Xue; Fu, Wen-Dong; Zhang, Yu; Zhang, Jing; Wang, Zhen; Li, Tian-Sen; Chen, Chuang-Fu; Guo, Fei; Zhang, Hui

    2015-08-01

    Brucella spp. are Gram-negative intracellular pathogens of both humans and animals that cause great economic burdens in developing countries. Live attenuated vaccines are the most efficient means for the prevention and control of animal Brucellosis. However, Brucella vaccines (strain M5-90 and others) have several drawbacks and do not allow serological differentiation between vaccinated and infected animals. A wboA mutant was derived from Brucella melitensis (B. melitensis) vaccine strain M5-90 and tested for virulence and protective efficiency. T-cell responses (CD4(+), CD8(+)), levels of immunoglobulin G (IgG), and cytokine production were observed. WboA was also assessed as a diagnostic marker for Brucellosis. B. melitensis strain M5-90ΔwboA exhibited reduced survival in murine macrophages (RAW 264.7) and BALB/c mice and induced protective immunity in mice comparable to that from the parental strain M5-90. In mice, the wboA mutant elicited an anti-Brucella-specific IgG response and induced the secretion of gamma interferon (IFN-γ) and interleukin-2 (IL-2). In sheep, M5-90ΔwboA immunization induced the secretion of IFN-γ, and serum samples from sheep inoculated with M5-90ΔwboA were negative by Bengal Plate Test (RBPT) and Standard Tube Agglutination Test (STAT). In mice, probes against WboA antigen allowed for serological differentiation between natural infection and vaccination. The M5-90ΔwboA mutant is a potential attenuated live vaccine candidate against virulent B. melitensis 16M infection. It will be further evaluated in livestock.

  12. A novel multiplex poliovirus binding inhibition assay applicable for large serosurveillance and vaccine studies, without the use of live poliovirus.

    PubMed

    Schepp, Rutger M; Berbers, Guy A M; Ferreira, José A; Reimerink, Johan H; van der Klis, Fiona R

    2017-03-01

    Large-scale serosurveillance or vaccine studies for poliovirus using the "gold standard" WHO neutralisation test (NT) are very laborious and time consuming. With the polio eradication at hand and with the removal of live attenuated Sabin strains from the oral poliovirus vaccine (OPV), starting with type 2 (as of April 2016), laboratories will need to conform to much more stringent laboratory biosafety regulations when handling live poliovirus strains. In this study, a poliovirus binding inhibition multiplex immunoassay (polio MIA) using inactivated poliovirus vaccine (IPV-Salk) was developed for simultaneous quantification of serum antibodies directed to all three poliovirus types. Our assay shows a good correlation with the NT and an excellent correlation with the ELISA-based binding inhibition assay (POBI). The assay is highly type-specific and reproducible. Additionally, serum sample throughput increases about fivefold relative to NT and POBI and the amount of serum needed is reduced by more than 90%. In conclusion, the polio MIA can be used as a safe and high throughput application, especially for large-scale surveillance and vaccine studies, reducing laboratory time and serum amounts needed.

  13. Avian metapneumovirus M2:2 protein inhibits replication in Vero cells: modification facilitates live vaccine development.

    PubMed

    Clubbe, Jayne; Naylor, Clive J

    2011-11-28

    Throughout the world, avian metapneumovirus (AMPV) infection of subtype A is principally controlled by two live vaccines both derived from UK field strain #8544. Improvements of those vaccines by use of reverse genetics technology was found to be hampered by the inability of #8544 to replicate in the commonly exploited Vero cell based reverse genetics system. A systematic reverse genetics based genome modification of a DNA copy of #8544, employing sequence data from a Vero grown, #8544 derived, live vaccine; was used to determine mutations required to facilitate virus recovery and replication in Vero cells. This identified a single coding substitution in the M2:2 reading frame as responsible. Furthermore, ablation of M2:2 was found to elicit the same outcome. M2:2 sequence analysis of seven AMPVs found Vero cell adaption to be associated with non similar amino acid changes in M2:2. The study shows that M2:2 modification of field virus #8544 will enable research leading to improved vaccines. This may have more general application to other AMPV field strains.

  14. A live RSV vaccine with engineered thermostability is immunogenic in cotton rats despite high attenuation.

    PubMed

    Stobart, Christopher C; Rostad, Christina A; Ke, Zunlong; Dillard, Rebecca S; Hampton, Cheri M; Strauss, Joshua D; Yi, Hong; Hotard, Anne L; Meng, Jia; Pickles, Raymond J; Sakamoto, Kaori; Lee, Sujin; Currier, Michael G; Moin, Syed M; Graham, Barney S; Boukhvalova, Marina S; Gilbert, Brian E; Blanco, Jorge C G; Piedra, Pedro A; Wright, Elizabeth R; Moore, Martin L

    2016-12-21

    Respiratory syncytial virus (RSV) is a leading cause of infant hospitalization and there remains no pediatric vaccine. RSV live-attenuated vaccines (LAVs) have a history of safe testing in infants; however, achieving an effective balance of attenuation and immunogenicity has proven challenging. Here we seek to engineer an RSV LAV with enhanced immunogenicity. Genetic mapping identifies strain line 19 fusion (F) protein residues that correlate with pre-fusion antigen maintenance by ELISA and thermal stability of infectivity in live RSV. We generate a LAV candidate named OE4 which expresses line 19F and is attenuated by codon-deoptimization of non-structural (NS1 and NS2) genes, deletion of the small hydrophobic (SH) gene, codon-deoptimization of the attachment (G) gene and ablation of the secreted form of G. OE4 (RSV-A2-dNS1-dNS2-ΔSH-dGm-Gsnull-line19F) exhibits elevated pre-fusion antigen levels, thermal stability, immunogenicity, and efficacy despite heavy attenuation in the upper and lower airways of cotton rats.

  15. A live RSV vaccine with engineered thermostability is immunogenic in cotton rats despite high attenuation

    PubMed Central

    Stobart, Christopher C.; Rostad, Christina A.; Ke, Zunlong; Dillard, Rebecca S.; Hampton, Cheri M.; Strauss, Joshua D.; Yi, Hong; Hotard, Anne L.; Meng, Jia; Pickles, Raymond J.; Sakamoto, Kaori; Lee, Sujin; Currier, Michael G.; Moin, Syed M.; Graham, Barney S.; Boukhvalova, Marina S.; Gilbert, Brian E.; Blanco, Jorge C. G.; Piedra, Pedro A.; Wright, Elizabeth R.; Moore, Martin L.

    2016-01-01

    Respiratory syncytial virus (RSV) is a leading cause of infant hospitalization and there remains no pediatric vaccine. RSV live-attenuated vaccines (LAVs) have a history of safe testing in infants; however, achieving an effective balance of attenuation and immunogenicity has proven challenging. Here we seek to engineer an RSV LAV with enhanced immunogenicity. Genetic mapping identifies strain line 19 fusion (F) protein residues that correlate with pre-fusion antigen maintenance by ELISA and thermal stability of infectivity in live RSV. We generate a LAV candidate named OE4 which expresses line 19F and is attenuated by codon-deoptimization of non-structural (NS1 and NS2) genes, deletion of the small hydrophobic (SH) gene, codon-deoptimization of the attachment (G) gene and ablation of the secreted form of G. OE4 (RSV-A2-dNS1-dNS2-ΔSH-dGm-Gsnull-line19F) exhibits elevated pre-fusion antigen levels, thermal stability, immunogenicity, and efficacy despite heavy attenuation in the upper and lower airways of cotton rats. PMID:28000669

  16. Protection of Cattle against Rinderpest by Vaccination with Wild-Type but Not Attenuated Strains of Peste des Petits Ruminants Virus

    PubMed Central

    Holzer, Barbara; Hodgson, Sophia; Logan, Nicola; Willett, Brian

    2016-01-01

    ABSTRACT Although rinderpest virus (RPV) has been eradicated in the wild, efforts are still continuing to restrict the extent to which live virus is distributed in facilities around the world and to prepare for any reappearance of the disease, whether through deliberate or accidental release. In an effort to find an alternative vaccine which could be used in place of the traditional live attenuated RPV strains, we have determined whether cattle can be protected from rinderpest by inoculation with vaccine strains of the related morbillivirus, peste des petits ruminants virus (PPRV). Cattle were vaccinated with wild-type PPRV or either of two established PPRV vaccine strains, Nigeria/75/1 or Sungri/96. All animals developed antibody and T cell immune responses to the inoculated PPRV. However, only the animals given wild-type PPRV were protected from RPV challenge. Animals given PPRV/Sungri/96 were only partially protected, and animals given PPRV/Nigeria/75/1 showed no protection against RPV challenge. While sera from animals vaccinated with the vaccine strain of RPV showed cross-neutralizing ability against PPRV, none of the sera from animals vaccinated with any strain of PPRV was able to neutralize RPV although sera from animals inoculated with wild-type PPRV were able to neutralize RPV-pseudotyped vesicular stomatitis virus. IMPORTANCE Rinderpest virus has been eradicated, and it is only the second virus for which this is so. Significant efforts are still required to ensure preparedness for a possible escape of RPV from a laboratory or its deliberate release. Since RPV vaccine protects sheep and goats from PPRV, it is important to determine if the reverse is true as this would provide a non-RPV vaccine for dealing with suspected RPV outbreaks. This is probably the last in vivo study with live RPV that will be approved. PMID:26984722

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

    PubMed

    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.

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

    PubMed

    Olsen, S C; Johnson, C S

    2012-06-01

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

  19. Immune effects of the vaccine of live attenuated Aeromonas hydrophila screened by rifampicin on common carp (Cyprinus carpio L).

    PubMed

    Jiang, Xinyu; Zhang, Chao; Zhao, Yanjing; Kong, Xianghui; Pei, Chao; Li, Li; Nie, Guoxing; Li, Xuejun

    2016-06-08

    Aeromonas hydrophila, as a strong Gram-negative bacterium, can infect a wide range of freshwater fish, including common carp Cyprinus carpio, and cause the huge economic loss. To create the effective vaccine is the best way to control the outbreak of the disease caused by A. hydrophila. In this study, a live attenuated A. hydrophila strain, XX1LA, was screened from the pathogenic A. hydrophila strain XX1 cultured on medium containing the antibiotic rifampicin, which was used as a live attenuated vaccine candidate. The immune protection of XX1LA against the pathogen A. hydrophila in common carp was evaluated by the relative percent survival (RPS), the specific IgM antibody titers, serum lysozyme activity and the expression profiles of multiple immune-related genes at the different time points following immunization. The results showed that the variable up-regulations of the immune-related genes, such as the pro-inflammatory cytokine IL-1β, the chemokine IL-10 and IgM, were observed in spleen and liver of common carp injected in the vaccines with the formalin-killed A. hydrophila (FKA) and the live attenuated XX1LA. Specific antibody to A. hydrophila was found to gradually increase during 28 days post-vaccination (dpv), and the RPS (83.7%) in fish vaccinated with XX1LA, was significant higher than that (37.2%) in fish vaccinated with FKA (P<0.05) on Day 28 after challenged by pathogen. It was demonstrated that the remarkable immune protection presented in the group vaccinated with XX1LA. During the late stage of 4-week immunization phase, compared with FKA and the control, specific IgM antibody titers significantly increased (P<0.05) in the XX1LA group. The activity of the lysozyme in serum indicated no significant change among three groups. In summary, the live attenuated bacterial vaccine XX1LA, screened in this study, indicates the better protect effect on common carp against A. hydrophila, which can be applied in aquaculture of common carp to prevent from the

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  1. Influence of antibiotics used as feed additives on the immune effect of erysipelas live vaccine in swine.

    PubMed

    Yamamoto, K; Takagi, M; Endoh, Y S; Kijima, M; Takahashi, T

    2000-08-01

    To investigate the influence of antibiotics used as feed additives on the immune response to erysipelas live vaccine, the pig inoculation test was applied. Avilamycin, oxytetracycline quaternary salt, enramycin, virginiamycin and tylosin phosphate were selected as test antibiotics. Five experimental feeds containing each antibiotic at the highest concentration permitted for feed additives in Japan, and the basal diet lacking antibiotics were examined. Twenty-nine pigs were divided into six groups. At first all the groups were fed with the antibiotic-free basal diet for 7 days, and then each group received the experimental feeds. On the 14th day after feeding with test feeds all the pigs, except for one control pig in each group, were immunized with the vaccine and all the pigs were then challenge-exposed to a virulent strain of Erysipelothrix rhusiopathiae 14 days after vaccination. The clinical response was observed every day for 14 days. In all the groups, most of the vaccinated pigs did not develop any clinical signs of acute erysipelas after the challenge exposure, whereas non-vaccinated control pigs died or showed severe generalized erythema with profound depression and anorexia. No differences in the protection against the challenge exposure were observed among the groups. Therefore, the present results suggest that these selected antibiotics would not interfere with the immune effect of the vaccine if given at the usual concentrations used for feed additives.

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

    PubMed

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

    2017-02-15

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

  3. Assessment of attenuated Salmonella vaccine strains in controlling experimental Salmonella Typhimurium infection in chickens.

    PubMed

    Pei, Yanlong; Parreira, Valeria R; Roland, Kenneth L; Curtiss, Roy; Prescott, John F

    2014-01-01

    Salmonella hold considerable promise as vaccine delivery vectors for heterologous antigens in chickens. Such vaccines have the potential additional benefit of also controlling Salmonella infection in immunized birds. As a way of selecting attenuated strains with optimal immunogenic potential as antigen delivery vectors, this study screened 20 novel Salmonella Typhimurium vaccine strains, differing in mutations associated with delayed antigen synthesis and delayed attenuation, for their efficacy in controlling colonization by virulent Salmonella Typhimurium, as well as for their persistence in the intestine and the spleen. Marked differences were observed between strains in these characteristics, which provide the basis for selection for further study as vaccine vectors.

  4. Effectiveness of Meningococcal B Vaccine against Endemic Hypervirulent Neisseria meningitidis W Strain, England

    PubMed Central

    Giuliani, Marzia Monica; Biolchi, Alessia; Pizza, Mariagrazia; Beebeejaun, Kazim; Lucidarme, Jay; Findlow, Jamie; Ramsay, Mary E.; Borrow, Ray

    2016-01-01

    Serum samples from children immunized with a meningococcal serogroup B vaccine demonstrated potent serum bactericidal antibody activity against the hypervirulent Neisseria meningitidis serogroup W strain circulating in England. The recent introduction of this vaccine into the United Kingdom national immunization program should also help protect infants against this endemic strain. PMID:26811872

  5. Development of live attenuated Streptococcus agalactiae vaccine for tilapia via continuous passage in vitro.

    PubMed

    Li, L P; Wang, R; Liang, W W; Huang, T; Huang, Y; Luo, F G; Lei, A Y; Chen, M; Gan, X

    2015-08-01

    Fish Streptococcus agalactiae (S. agalactiae) seriously harms the world's aquaculture industry and causes huge economic losses. This study aimed to develop a potential live attenuated vaccine of S. agalactiae. Pre-screened vaccine candidate strain S. agalactiae HN016 was used as starting material to generate an attenuated strain S. agalactiae YM001 by continuous passage in vitro. The biological characteristics, virulence, and stability of YM001 were detected, and the protective efficacy of YM001 immunization in tilapia was also determined. Our results indicated that the growth, staining, characteristics of pulsed-field gel electrophoresis (PFGE) genotype, and virulence of YM001 were changed significantly as compared to the parental strain HN016. High doses of YM001 by intraperitoneal (IP) injection (1.0 × 10(9) CFU/fish) and oral gavage (1.0 × 10(10) CFU/fish) respectively did not cause any mortality and morbidity in tilapia. The relative percent survivals (RPSs) of fishes immunized with YM001 (1.0 × 10(8) CFU/fish, one time) via injection, immersion, and oral administration were 96.88, 67.22, and 71.81%, respectively, at 15 days, and 93.61, 60.56, and 53.16%, respectively, at 30 days. In all tests with 1-3 times of immunization in tilapia, the dosages at 1 × 10(8) and 1 × 10(9) CFU/fish displayed the similar best results, whereas the immunoprotection of the dosages at 1 × 10(6) and 1 × 10(7) CFU/fish declined significantly (P < 0.01), and 1 × 10(5) CFU/fish hardly displayed any protective effect. In addition, the efficacy of 2-3 times of immunization was significantly higher than that of single immunization (P < 0.01) while no significant difference in the efficacy between twice and thrice of immunization was seen (P > 0.05). The level of protective antibody elicited by oral immunization was significantly higher compared to that of the control group (P < 0.01), and the antibody reached their maximum levels 14-21 days after the immunization but decreased

  6. Oral Fluids as a Live-Animal Sample Source for Evaluating Cross-Reactivity and Cross-Protection following Intranasal Influenza A Virus Vaccination in Pigs.

    PubMed

    Hughes, Holly R; Vincent, Amy L; Brockmeier, Susan L; Gauger, Phillip C; Pena, Lindomar; Santos, Jefferson; Braucher, Douglas R; Perez, Daniel R; Loving, Crystal L

    2015-10-01

    In North American swine, there are numerous antigenically distinct H1 influenza A virus (IAV) variants currently circulating, making vaccine development difficult due to the inability to formulate a vaccine that provides broad cross-protection. Experimentally, live-attenuated influenza virus (LAIV) vaccines demonstrate increased cross-protection compared to inactivated vaccines. However, there is no standardized assay to predict cross-protection following LAIV vaccination. Hemagglutination-inhibiting (HI) antibody in serum is the gold standard correlate of protection following IAV vaccination. LAIV vaccination does not induce a robust serum HI antibody titer; however, a local mucosal antibody response is elicited. Thus, a live-animal sample source that could be used to evaluate LAIV immunogenicity and cross-protection is needed. Here, we evaluated the use of oral fluids (OF) and nasal wash (NW) collected after IAV inoculation as a live-animal sample source in an enzyme-linked immunosorbent assay (ELISA) to predict cross-protection in comparison to traditional serology. Both live-virus exposure and LAIV vaccination provided heterologous protection, though protection was greatest against more closely phylogenetically related viruses. IAV-specific IgA was detected in NW and OF samples and was cross-reactive to representative IAV from each H1 cluster. Endpoint titers of cross-reactive IgA in OF from pigs exposed to live virus was associated with heterologous protection. While LAIV vaccination provided significant protection, LAIV immunogenicity was reduced compared to live-virus exposure. These data suggest that OF from pigs inoculated with wild-type IAV, with surface genes that match the LAIV seed strain, could be used in an ELISA to assess cross-protection and the antigenic relatedness of circulating and emerging IAV in swine.

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    2014-06-17

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

  9. Herpes zoster caused by vaccine-strain varicella zoster virus in an immunocompetent recipient of zoster vaccine.

    PubMed

    Tseng, Hung Fu; Schmid, D Scott; Harpaz, Rafael; LaRussa, Philip; Jensen, Nancy J; Rivailler, Pierre; Radford, Kay; Folster, Jennifer; Jacobsen, Steven J

    2014-04-01

    We report the first laboratory-documented case of herpes zoster caused by the attenuated varicella zoster virus (VZV) contained in Zostavax in a 68-year-old immunocompetent adult with strong evidence of prior wild-type VZV infection. The complete genome sequence of the isolate revealed that the strain carried 15 of 42 (36%) recognized varicella vaccine-associated single-nucleotide polymorphisms, including all 5 of the fixed vaccine markers present in nearly all of the strains in the vaccine. The case of herpes zoster was relatively mild and resolved without complications.

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

    PubMed

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

    2015-05-01

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

  11. Controversial results of the genetic analysis of a canine distemper vaccine strain.

    PubMed

    Demeter, Zoltán; Palade, Elena Alina; Hornyák, Akos; Rusvai, Miklós

    2010-05-19

    Canine distemper (CD) is a highly contagious, often fatal, multisystemic viral disease of receptive carnivores. The presence of a PsiI cleavage site on a specific location of the hemagglutinin (H) gene was found to be a hallmark of vaccine strains, thus, a previously published restriction fragment length polymorphism (RFLP) test using PsiI theoretically allows the distinction between all currently used vaccine strains and virulent field strains. The RFLP test was carried out on all brands of CD vaccines available in Hungary. The present work describes the extensive sequencing and phylogenetic study of the strain present in Vanguard (Pfizer Animal Health) vaccines, which following the PsiI based RFLP test reacted as a wild-type strain. Based on the product description provided by the manufacturer, all batches should have contained a virus strain (Snyder Hill) belonging to the group of vaccine strains (America-1). Extensive genetic analysis involving the full nucleic acid sequence of four other genes (N, M, P and F) of the CDV genome revealed that the incriminated virus strain showed a higher level of genetic identity to wild-type strains from the America-2 group than to any of the strains belonging to America-1 group, therefore the vaccine does not contain the virus strain stated by the manufacturer in its product description and has not been containing it since at least 1992.

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

    PubMed

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

    2012-07-15

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

  13. Characterization of Erysipelothrix Species Isolates from Clinically Affected Pigs, Environmental Samples, and Vaccine Strains from Six Recent Swine Erysipelas Outbreaks in the United States ▿

    PubMed Central

    Bender, J. S.; Shen, H. G.; Irwin, C. K.; Schwartz, K. J.; Opriessnig, T.

    2010-01-01

    The aim of this study was to characterize Erysipelothrix sp. isolates from clinically affected pigs and their environment and compare them to the Erysipelothrix sp. vaccines used at the sites. Samples were collected during swine erysipelas outbreaks in vaccinated pigs in six Midwest United States swine operations from 2007 to 2009. Pig tissue samples were collected from 1 to 3 pigs from each site. Environmental samples (manure, feed, central-line water, oral fluids, and swabs collected from walls, feed lines, air inlets, exhaust fans, and nipple drinkers) and live vaccine samples were collected following the isolation of Erysipelothrix spp. from clinically affected pigs. All Erysipelothrix sp. isolates obtained were further characterized by serotyping. Selected isolates were further characterized by PCR assays for genotype (E. rhusiopathiae, E. tonsillarum, Erysipelothrix sp. strain 1, and Erysipelothrix sp. strain 2) and surface protective antigen (spa) type (A, B1, B2, and C). All 26 isolates obtained from affected pigs were E. rhusiopathiae, specifically, serotypes 1a, 1b, 2, and 21. From environmental samples, 56 isolates were obtained and 52/56 were E. rhusiopathiae (serotypes 1a, 1b, 2, 6, 9, 12, and 21), 3/56 were Erysipelothrix sp. strain 1 (serotypes 13 and untypeable), and one was a novel species designated Erysipelothrix sp. strain 3 (serotype untypeable). Four of six vaccines used at the sites were commercially available products and contained live E. rhusiopathiae serotype 1a. Of the remaining two vaccines, one was an autogenous live vaccine and contained live E. rhusiopathiae serotype 2 and one was a commercially produced inactivated vaccine and was described by the manufacturer to contain serotype 2 antigen. All E. rhusiopathiae isolates were positive for spaA. All Erysipelothrix sp. strain 1 isolates and the novel Erysipelothrix sp. strain 3 isolate were negative for all currently known spa types (A, B1, B2, and C). These results indicate that

  14. Effect of genotype specific live recombinant Newcastle disease vaccines on virus shedding after challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All Newcastle disease viruses (NDVs) are part of a single serotype; however, current vaccine strains display between 15 and 18% amino acid differences at the F and HN protein compared with current virulent viruses. Previous studies have shown that increased amino acid similarity between NDV vaccine...

  15. Development of a duplex PCR for rapid detection and differentiation of Erysipelothrix rhusiopathiae vaccine strains and wild type strains.

    PubMed

    Zhu, Weifeng; Wu, Chao; Kang, Chao; Cai, Chengzhi; Jin, Meilin

    2017-02-01

    The differentiation of vaccine strains from wild type strains is important for disease control. A duplex PCR for rapid detection and differentiation of Erysipelothrix rhusiopathiae vaccine strains and wild type strains was developed based on the DNA polymerase IV gene. This duplex PCR was sensitive and specific. The detection results were coincident with that of a single nucleotide polymorphisms based PCR but the detection process was more rapid. In conclusion, this duplex PCR was a useful tool for Erysipelothrix rhusiopathiae infections' differential diagnosis in China.

  16. WHO informal consultation on quality, safety and efficacy specifications for live attenuated rotavirus vaccines Mexico City, Mexico, 8-9 February 2005.

    PubMed

    Wood, David

    2005-12-01

    Rotavirus vaccines are at an advanced stage of development but there are as yet no WHO recommendations on production and quality control to provide regulatory guidance. A meeting of experts was convened by WHO and PAHO/AMRO to review the scientific basis for production and quality control of rotavirus vaccines, and to discuss specific measures to assure the safety and efficacy of rotavirus vaccines. The meeting was attended by 25 experts from 14 countries, drawn from academia, public health, national regulatory authorities and vaccine producers. It was agreed that existing guidance for other live virus vaccines provides a very good basis for product characterization, especially for source materials and control of production. The basis for attenuation of current vaccines or vaccine candidates is not known but, at least for the vaccines based on the Jennerian approach of using animal (bovine) rotaviruses, is likely to be multigenic. The risk of intussusception in humans is influenced by genetic background and age. Recent analyzes of large vaccine safety trials found that certain strains of vaccine virus were not associated with intussusception, although in these trials the first dose of vaccine was not administered to children over 3 months of age. Since age is a risk factor for intussusception, this may suggest that early delivery of the first dose of vaccine is desirable. However, maternal antibodies may mitigate against early delivery of the first vaccine dose. Factors which could affect vaccine efficacy or safety include strain diversity, malnutrition, other enteric infections, parasitic infection or immune suppression. It was concluded that data from clinical trials conducted in one part of the world would not necessarily be predictive of vaccine efficacy in other places. It was agreed that in nonclinical evaluations there was a need to use oral dosing for toxicity studies and, because rotavirus is non-neurovirulent, that there was no need for an animal

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

    PubMed

    Yazbak, F Edward; Diodati, Catherine J M

    2002-09-01

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

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

    PubMed

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

    2016-11-01

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

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

    PubMed

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

    2014-02-01

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

  20. Genome sequence of Bacillus anthracis attenuated vaccine strain A16R used for human in China.

    PubMed

    Liu, Xiankai; Qi, Xinpeng; Zhu, Li; Wang, Dongshu; Gao, Zhiqi; Deng, Haijun; Wu, Weili; Hu, Tao; Chen, Chen; Chen, Weijun; Wang, Hengliang

    2015-09-20

    An attenuated Bacillus anthracis vaccine strain for human use, A16R, was obtained in China after ultraviolet radiation treatment and continuous subculture of the wild-type strain A16. A16R can synthesize the exotoxin, but without a capsule. We sequenced and annotated the A16R genome to encourage the use of this strain. The genome sequencing of the wild-type strain A16 is underway and the genomic comparison between the two strains will help to illustrate the attenuating mechanism of the A16R vaccine strain.

  1. Selecting vaccine strains for H3N2 human influenza A virus.

    PubMed

    Suzuki, Yoshiyuki

    2015-06-01

    H3N2 human influenza A virus causes epidemics of influenza mainly in the winter season in temperate regions. Since the antigenicity of this virus evolves rapidly, several attempts have been made to predict the major amino acid sequence of hemagglutinin 1 (HA1) in the target season of vaccination. However, the usefulness of predicted sequence was unclear because its relationship to the antigenicity was unknown. Here the antigenic model for estimating the degree of antigenic difference (antigenic distance) between amino acid sequences of HA1 was integrated into the process of selecting vaccine strains for H3N2 human influenza A virus. When the effectiveness of a potential vaccine strain for a target season was evaluated retrospectively using the average antigenic distance between the strain and the epidemic viruses sampled in the target season, the most effective vaccine strain was identified mostly in the season one year before the target season (pre-target season). Effectiveness of actual vaccines appeared to be lower than that of the strains randomly chosen in the pre-target season on average. It was recommended to replace the vaccine strain for every target season with the strain having the smallest average antigenic distance to the others in the pre-target season. The procedure of selecting vaccine strains for future epidemic seasons described in the present study was implemented in the influenza virus forecasting system (INFLUCAST) (http://www.nsc.nagoya-cu.ac.jp/~yossuzuk/influcast.html).

  2. Rovac is the possible ancestor of the Russian lapinized vaccines LK-VNIVViM and CS strains but not the Chinese strain (C-strain) vaccine against classical swine fever.

    PubMed

    Zhou, Weiguang; Gao, Shandian; Podgórska, Katarzyna; Stadejek, Tomasz; Qiu, Hua-Ji; Yin, Hong; Drew, Trevor; Liu, Lihong

    2014-11-20

    Classical swine fever (CSF), or hog cholera, is a highly contagious disease that emerged in the first half of the nineteenth century. To fight against the disease and protect pigs, different vaccines were developed, including early generation of lapinized Rovac strain and the later development of the “Chinese” strain (C-strain). However, details of the development of these vaccines are lost in history. In order to investigate the phylogenetic relationship between the Rovac and other lapinized vaccines, this study determined the genome sequence of the Rovac, which comprised 12,304 nucleotides, notably with the 3′untranslated region (3′UTR) containing a 13-nucleotide insertion. The near-complete genome of Russian vaccine strain LK-VNIVViM was determined by next-generation sequencing on Illumina MiSeq platform. Whole genome phylogenetic analysis revealed a closer relationship of the Rovac strain with the Russian LK-VNIVViM, CS strain and its derivative RUCSFPLUM (genotype 1.2), rather than with the C-strain (genotype 1.1). In addition, it demonstrated an ancestry role of the LK-VNIVViM in relation to the CS strain and RUCSFPLUM. The study suggested that the Rovac vaccine is the possible ancestor of the Russian vaccine strains but not the C-strain vaccine.

  3. Neutralizing Antibody Responses to Antigenically Drifted Influenza A(H3N2) Viruses among Children and Adolescents following 2014-2015 Inactivated and Live Attenuated Influenza Vaccination

    PubMed Central

    Martin, Judith M.; Gross, F. Liaini; Jefferson, Stacie; Cole, Kelly Stefano; Archibald, Crystal Ann; Nowalk, Mary Patricia; Susick, Michael; Moehling, Krissy; Spencer, Sarah; Chung, Jessie R.; Flannery, Brendan; Zimmerman, Richard K.

    2016-01-01

    Human influenza A(H3N2) viruses that predominated during the moderately severe 2014-2015 influenza season differed antigenically from the vaccine component, resulting in reduced vaccine effectiveness (VE). To examine antibody responses to 2014-2015 inactivated influenza vaccine (IIV) and live-attenuated influenza vaccine (LAIV) among children and adolescents, we collected sera before and after vaccination from 150 children aged 3 to 17 years enrolled at health care facilities. Hemagglutination inhibition (HI) assays were used to assess the antibody responses to vaccine strains. We evaluated cross-reactive antibody responses against two representative A(H3N2) viruses that had antigenically drifted from the A(H3N2) vaccine component using microneutralization (MN) assays. Postvaccination antibody titers to drifted A(H3N2) viruses were higher following receipt of IIV (MN geometric mean titers [GMTs], 63 to 68; 38 to 45% achieved seroconversion) versus LAIV (MN GMT, 22; only 3 to 5% achieved seroconversion). In 9- to 17-year-olds, the highest MN titers were observed among IIV-vaccinated individuals who had received LAIV in the previous season. Among all IIV recipients aged 3 to 17 years, the strongest predictor of antibody responses to the drifted viruses was the prevaccination titers to the vaccine strain. The results of our study suggest that in an antigenically drifted influenza season, vaccination still induced cross-reactive antibody responses to drifted circulating A(H3N2) viruses, although higher antibody titers may be required for protection. Antibody responses to drifted A(H3N2) viruses following vaccination were influenced by multiple factors, including vaccine type and preexisting immunity from prior exposure. PMID:27558294

  4. Neutrophils rapidly migrate via lymphatics after Mycobacterium bovis BCG intradermal vaccination and shuttle live bacilli to the draining lymph nodes.

    PubMed

    Abadie, Valérie; Badell, Edgar; Douillard, Patrice; Ensergueix, Danielle; Leenen, Pieter J M; Tanguy, Myriam; Fiette, Laurence; Saeland, Sem; Gicquel, Brigitte; Winter, Nathalie

    2005-09-01

    The early innate response after Mycobacterium bovis bacille Calmette-Guérin (BCG) vaccination is poorly characterized but probably decisive for subsequent protective immunity against tuberculosis. Therefore, we vaccinated mice with fluorescent BCG strains in the ear dorsum, as a surrogate of intradermal vaccination in humans. During the first 3 days, we tracked BCG host cells migrating out of the dermis to the auricular draining lymph nodes (ADLNs). Resident skin dendritic cells (DCs) or macrophages did not play a predominant role in early BCG capture and transport to ADLNs. The main BCG host cells rapidly recruited both in the dermis and ADLNs were neutrophils. Fluorescent green or red BCG strains injected into nonoverlapping sites were essentially sheltered by distinct neutrophils in the ADLN capsule, indicating that neutrophils had captured bacilli in peripheral tissue and transported them to the lymphoid organ. Strikingly, we observed BCG-infected neutrophils in the lumen of lymphatic vessels by confocal microscopy on ear dermis. Fluorescence-labeled neutrophils injected into the ears accumulated exclusively into the ipsilateral ADLN capsule after BCG vaccination. Thus, we provide in vivo evidence that neutrophils, like DCs or inflammatory monocytes, migrate via afferent lymphatics to lymphoid tissue and can shuttle live microorganisms.

  5. A live-attenuated influenza vaccine for H3N2 canine influenza virus.

    PubMed

    Rodriguez, Laura; Nogales, Aitor; Reilly, Emma C; Topham, David J; Murcia, Pablo R; Parrish, Colin R; Martinez Sobrido, Luis

    2017-04-01

    Canine influenza is a contagious respiratory disease in dogs caused by two subtypes (H3N2 and H3N8) of canine influenza virus (CIV). Currently, only inactivated influenza vaccines (IIVs) are available for the prevention of CIVs. Historically, live-attenuated influenza vaccines (LAIVs) have been shown to produce better immunogenicity and protection efficacy than IIVs. Here, we have engineered a CIV H3N2 LAIV by using the internal genes of a previously described CIV H3N8 LAIV as a master donor virus (MDV) and the surface HA and NA genes of a circulating CIV H3N2 strain. Our findings show that CIV H3N2 LAIV replicates efficiently at low temperature but its replication is impaired at higher temperatures. The CIV H3N2 LAIV was attenuated in vivo but induced better protection efficacy in mice against challenge with wild-type CIV H3N2 than a commercial CIV H3N2 IIV. This is the first description of a LAIV for the prevention of CIV H3N2 in dogs.

  6. Temperature-sensitive mutations for live-attenuated Rift Valley fever vaccines: implications from other RNA viruses

    PubMed Central

    Nishiyama, Shoko; Ikegami, Tetsuro

    2015-01-01

    Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to the African continent. RVF is characterized by high rate of abortions in ruminants and hemorrhagic fever, encephalitis, or blindness in humans. RVF is caused by the Rift Valley fever virus (RVFV: genus Phlebovirus, family Bunyaviridae). Vaccination is the only known effective strategy to prevent the disease, but there are no licensed RVF vaccines available for humans. A live-attenuated vaccine candidate derived from the wild-type pathogenic Egyptian ZH548 strain, MP-12, has been conditionally licensed for veterinary use in the U.S. MP-12 displays a temperature-sensitive (ts) phenotype and does not replicate at 41°C. The ts mutation limits viral replication at a specific body temperature and may lead to an attenuation of the virus. Here we will review well-characterized ts mutations for RNA viruses, and further discuss the potential in designing novel live-attenuated vaccines for RVF. PMID:26322023

  7. Temperature-sensitive mutations for live-attenuated Rift Valley fever vaccines: implications from other RNA viruses.

    PubMed

    Nishiyama, Shoko; Ikegami, Tetsuro

    2015-01-01

    Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to the African continent. RVF is characterized by high rate of abortions in ruminants and hemorrhagic fever, encephalitis, or blindness in humans. RVF is caused by the Rift Valley fever virus (RVFV: genus Phlebovirus, family Bunyaviridae). Vaccination is the only known effective strategy to prevent the disease, but there are no licensed RVF vaccines available for humans. A live-attenuated vaccine candidate derived from the wild-type pathogenic Egyptian ZH548 strain, MP-12, has been conditionally licensed for veterinary use in the U.S. MP-12 displays a temperature-sensitive (ts) phenotype and does not replicate at 41°C. The ts mutation limits viral replication at a specific body temperature and may lead to an attenuation of the virus. Here we will review well-characterized ts mutations for RNA viruses, and further discuss the potential in designing novel live-attenuated vaccines for RVF.

  8. Real-time RT-PCR assays to differentiate wild-type group A rotavirus strains from Rotarix(®) and RotaTeq(®) vaccine strains in stool samples.

    PubMed

    Gautam, Rashi; Esona, Mathew D; Mijatovic-Rustempasic, Slavica; Ian Tam, Ka; Gentsch, Jon R; Bowen, Michael D

    2014-01-01

    Group A rotaviruses (RVA) are the leading cause of severe diarrhea in young children worldwide. Two live-attenuated RVA vaccines, Rotarix(®) and RotaTeq(®) are recommended by World Health Organization (WHO) for routine immunization of all infants. Rotarix(®) and RotaTeq(®) vaccines have substantially reduced RVA associated mortality but occasionally have been associated with acute gastroenteritis (AGE) cases identified in vaccinees and their contacts. High-throughput assays are needed to monitor the prevalence of vaccine strains in AGE cases and emergence of new vaccine-derived strains following RVA vaccine introduction. In this study, we have developed quantitative real-time RT-PCR (qRT-PCR) assays for detection of Rotarix(®) and RotaTeq(®) vaccine components in stool samples. Real-time RT-PCR assays were designed for vaccine specific targets in the genomes of Rotarix(®) (NSP2, VP4) and RotaTeq(®) (VP6, VP3-WC3, VP3-human) and validated on sequence confirmed stool samples containing vaccine strains, wild-type RVA strains, and RVA-negative stools. For quantification, standard curves were generated using dsRNA transcripts derived from RVA gene segments. Rotarix(®) NSP2 and VP4 qRT-PCR assays exhibited 92-100% sensitivity, 99-100% specificity, 94-105% efficiency, and a limit of detection of 2-3 copies per reaction. RotaTeq(®) VP6, VP3-WC3, and VP3-human qRT-PCR assays displayed 100% sensitivity, 94-100% specificity, 91-102% efficiency and limits of detection of 1 copy, 2 copies, and 140 copies, respectively. These assays permit rapid identification of Rotarix(®) and RotaTeq(®) vaccine components in stool samples from clinical and surveillance studies and will be helpful in determining the frequency of vaccine strain-associated AGE.

  9. Study of live recombinant cold-adapted influenza bivalent vaccine of type A for use in children: an epidemiological control trial.

    PubMed

    Alexandrova, G I; Budilovsky, G N; Koval, T A; Polezhaev, F I; Garmashova, L M; Ghendon YuZ; Romanova, Y R; Smorodintsev, A A

    1986-06-01

    Live cold-adapted recombinant bivalent vaccine of influenza type A was studied in a controlled field trial in 1982-1983 among nearly 30,000 children 3-15 years old. The bivalent vaccine consisted of recombinants 47/25/1 (H1N1) and 47/7/2 (H3N2) of wild-type viruses A/Brazil/11/78 (H1N1) and A/Bangkok/1/79 (H3N2) with cold-adapted donor A/Leningrad/134/47/57 (H2N2). The recombinants which received mutant nonglycoprotein genes from cold-adapted donor did not suppress each other after simultaneous inoculation of children and stimulated antibody response to both strains. The bivalent vaccine was completely attenuated for children. It caused less than 1% transient febrile reactions during five days after the first vaccination, including double seronegative individuals with low antibody titres to both vaccinal strains. The cold-adapted bivalent vaccine tested proved to be safe for children according to the analysis of morbidity studies among vaccines and a control group performed during the five days and the following six months after the first immunization. There is a similar distribution of non-influenza illnesses and a statistically significant decrease in influenza-like diseases among vaccines compared to the control group. In the four months after the immunization programme was completed, epidemics of influenza A H1N1 and H3N2 occurred. The incidence of influenza-like diseases was approximately 50% less in the vaccinated than in the control groups. This is the first evidence of safety and protective efficacy of recombinant live influenza vaccine for children 3-15 years of age.

  10. Experimental Infection of Horses with an Attenuated Venezuelan Equine Encephalomyelitis Vaccine (Strain TC-83)

    PubMed Central

    Walton, Thomas E.; Alvarez, Otto; Buckwalter, Ross M.; Johnson, Karl M.

    1972-01-01

    Ten horses (Equus caballus) were vaccinated with strain TC-83 Venezuelan equine encephalomyelitis (VEE) virus vaccine. Febrile responses and leukopenia due to a reduction of lymphocytes and neutrophils were observed in all animals. Viremias were demonstrable in eight horses, with a maximum of 103.5 median tissue culture infectious dose units per ml of serum in two horses. Clinical illness with depression and anorexia were observed in five horses. Neutralizing (N), hemagglutination-inhibiting, and complement-fixing antibodies to the vaccine virus were demonstrable by 5, 6.5, and 7 days, respectively, after vaccination. Differential titrations of serum to six VEE strains revealed high titers of N antibody to vaccine virus, moderate titers to the epizootic Trinidad donkey no. 1 strain (VEE antigenic subtype I, variant A) from which TC-83 was derived, and low titers to two other epizootic strains (subtype I, variants B and C) in all horses at 1 month after vaccination; some animals responded with low levels of N antibody to the enzootic viruses (subtype I, variants D and E). Fourteen months after vaccination, six animals with detectable N antibody were challenged with MF-8 (subtype I, variant B), an epidemic-epizootic strain isolated in 1969 from a man in Honduras. All horses resisted challenge with the equine pathogenic strain of VEE. Marked increases of N antibody in most horses were demonstrable to some VEE strains when tested 1 month after challenge. PMID:4637604

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

    PubMed

    Zhou, Peifu; Xie, Jianping

    2014-01-01

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

  12. Genetic characterisation of attenuated SAD rabies virus strains used for oral vaccination of wildlife.

    PubMed

    Geue, Lutz; Schares, Susann; Schnick, Christina; Kliemt, Jeannette; Beckert, Aline; Freuling, Conrad; Conraths, Franz J; Hoffmann, Bernd; Zanoni, Reto; Marston, Denise; McElhinney, Lorraine; Johnson, Nicholas; Fooks, Anthony R; Tordo, Noel; Müller, Thomas

    2008-06-19

    The elimination of rabies from the red fox (Vulpes vulpes) in Western Europe has been achieved by the oral rabies vaccination (ORV) of wildlife with a range of attenuated rabies virus strains. With the exception of the vaccinia rabies glycoprotein recombinant vaccine (VRG), all strains were originally derived from a common ancestor; the Street Alabama Dufferin (SAD) field strain. However, after more than 30 years of ORV it is still not possible to distinguish these vaccine strains and there is little information on the genetic basis for their attenuation. We therefore sequenced and compared the full-length genome of five commercially available SAD vaccine viruses (SAD B19, SAD P5/88, SAG2, SAD VA1 and SAD Bern) and four other SAD strains (the original SAD Bern, SAD VA1, ERA and SAD 1-3670 Wistar). Nucleotide sequencing allowed identifying each vaccine strain unambiguously. Phylogenetic analysis revealed that the majority of the currently used commercial attenuated rabies virus vaccines appear to be derived from SAD B19 rather than from SAD Bern. One commercially available vaccine virus did not contain the SAD strain mentioned in the product information of the producer. Two SAD vaccine strains appeared to consist of mixed genomic sequences. Furthermore, in-del events targeting A-rich sequences (in positive strand) within the 3' non-coding regions of M and G genes were observed in SAD-derivates developed in Europe. Our data also supports the idea of a possible recombination that had occurred during the derivation of the European branch of SAD viruses. If confirmed, this recombination event would be the first one reported among RABV vaccine strains.

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

    PubMed

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

    2011-02-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

    Li, Jingliang; Liu, Guanchen; Liu, Xin; Yang, Jiaxin; Chang, Junliang; Zhang, Wenyan; Yu, Xiao-Fang

    2015-01-01

    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. PMID:26193302

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

    SciTech Connect

    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. . E-mail: dongj@genphar.com

    2006-09-30

    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{sup 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. Vaccination of rhesus macaques with the live-attenuated HSV-1 vaccine VC2 stimulates the proliferation of mucosal T cells and germinal center responses resulting in sustained production of highly neutralizing antibodies.

    PubMed

    Stanfield, Brent A; Pahar, Bapi; Chouljenko, Vladimir N; Veazey, Ronald; Kousoulas, Konstantin G

    2017-01-23

    We have shown that the live-attenuated HSV-1 VC2 vaccine strain with mutations in glycoprotein K (gK) and the membrane protein UL20 is unable to establish latency in vaccinated animals and produces a robust immune response capable of completely protecting mice against lethal vaginal HSV-1 or HSV-2 infections. To better understand the immune response generated by vaccination with VC2, we tested its ability to elicit immune responses in rhesus macaques. Vaccinated animals showed no signs of disease and developed increasing HSV-1 and HSV-2 reactive IgG1 after two booster vaccinations, while IgG subtypes IgG2 and IgG3 remained at low to undetectable levels. All vaccinated animals produced high levels of cross protective neutralizing antibodies. Flow cytometry analysis of cells isolated from draining lymph nodes showed that VC2 vaccination stimulated significant increases in plasmablast (CD27(high)CD38(high)) and mature memory (CD21(-)IgM(-)) B cells. T cell analysis on cells isolated from draining lymph node biopsies demonstrated a statistically significant increase in proliferating (Ki67(+)) follicular T helper cells and regulatory CXCR5(+) CD8(+) cytotoxic T cells. Analysis of plasma isolated two weeks post vaccination showed significant increases in circulating CXCL13 indicating increased germinal center activity. Cells isolated from vaginal biopsy samples collected over the course of the study exhibited vaccination-dependent increases in proliferating (Ki67(+)) CD4(+) and CD8(+) T cell populations. These results suggest that intramuscular vaccination with the live-attenuated HSV-1 VC2 vaccine strain can stimulate robust IgG1 antibody responses that persist for >250days post vaccination. In addition, vaccination lead to the maturation of B cells into plasmablast and mature memory B cells, the expansion of follicular T helper cells, and affects in the mucosal immune responses. These data suggest that the HSV VC2 vaccine induces potent immune responses that could help

  18. Salmonella abortusovis, strain Rv6, a new vaccinal vehicle for small ruminants.

    PubMed

    Bourgogne, A; Sanchis, R; Clément, J M; Pépin, M

    1998-03-31

    Salmonella abortusovis strain Rv6 (Sao Rv6) is a live attenuated vaccine used for a few years to protect ewes against abortive salmonellosis. As Salmonellae, particularly Salmonella aro mutants, have considerable potential as vehicles for the presentation of heterologous vaccine antigens, Sao Rv6 was tested in order to develop a vaccinal vehicle for small ruminants. Five vector plasmids were tested in Sao Rv6; these plasmids, which carry Maltose Binding Protein (MBP) expressed as protein, but differ in their promotors, had been previously tested in S. typhimurium strain SL3261, and were transferred into Sao Rv6. The five plasmids were stable in vitro, and the recombinant Sao Rv6 expressed MBP at various levels. Intraperitoneal infection of OF1 mice with the recombinant bacteria did not modify the characteristics of Sao Rv6; dissemination and infection levels were similar in all groups and all mice developed antibodies to Salmonella antigens as measured by ELISA. In contrast, only animals immunized with Sao Rv6 carrying the pNTE plasmid developed a serum antibody response to MBP. This plasmid was then tested in sheep; following subcutaneous immunization with Sao Rv6-pNTE, dissemination and infection levels were not modified in comparison with sheep immunized with Sao Rv6 lacking plasmid. Antibodies specific to MBP were detected in sera of sheep immunized with Sao Rv6-pNTE, purified MBP, and with S. typhimurium SL3261-pNTE as positive controls. These results demonstrate that Sao Rv6 can be used as a vehicle for heterologous antigens in sheep with pNTE as plasmid vector.

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

    PubMed

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

    2013-08-28

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

  20. Challenges of selecting seasonal influenza vaccine strains for humans with diverse pre-exposure histories

    PubMed Central

    Hensley, Scott E.

    2014-01-01

    Seasonal influenza vaccine strains are routinely updated when influenza viruses acquire mutations in exposed regions of the hemagglutinin and neuraminidase glycoproteins. Ironically, although thousands of viral isolates are sequenced each year, today's influenza surveillance community places less emphasis on viral genetic information and more emphasis on classical serological assays when choosing vaccine strains. Here, I argue that these classical serological assays are oversimplified and that they fail to detect influenza mutations that facilitate escape of particular types of human antibodies. I propose that influenza vaccine strains should be updated more frequently even when classical serological assays fail to detect significant antigenic alterations. PMID:25108824

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  2. Genotype characterization of commonly used Newcastle disease virus vaccine strains of India.

    PubMed

    Dey, Sohini; Chellappa, Madhan Mohan; Gaikwad, Satish; Kataria, Jag Mohan; Vakharia, Vikram N

    2014-01-01

    Newcastle disease is an avian pathogen causing severe economic losses to the Indian poultry industry due to recurring outbreaks in vaccinated and unvaccinated flocks. India being an endemic country, advocates vaccination against the virus using lentogenic and mesogenic strains. Two virus strains which are commonly used for vaccination are strain F (a lentogenic virus) and strain R2B (a mesogenic virus). Strain F is given to 0-7 days old chicks and R2B is given to older birds which are around 6-8 weeks old. To understand the genetic makeup of these two strains, a complete genome study and phylogenetic analysis of the F, HN genes of these vaccine strains were carried out. Both the viral strains had a genome length of 15,186 nucleotides and consisted of six genes with conserved complimentary 3' leader and 5' trailer regions. The fusion protein cleavage site of strain F is GGRQGRL and strain R2B is RRQKRF. Although both the viral strains had different virulence attributes, the length of the HN protein was similar with 577 amino acids. Phylogenetic analysis of F, HN and complete genome sequences grouped these two strains in genotype II category which are considered as early genotypes and corroborated with their years of isolation.

  3. Protection conferred by live infectious bronchitis vaccine viruses against variant Middle East IS/885/00-like and IS/1494/06-like isolates in commercial broiler chicks

    PubMed Central

    Awad, Faez; Forrester, Anne; Baylis, Matthew; Lemiere, Stephane; Ganapathy, Kannan

    2015-01-01

    The ability of the infectious bronchitis H120 (a Massachusetts strain) and CR88 (a 793B strain) live attenuated vaccine viruses to protect from two Middle East infectious bronchitis virus isolates, IS/885/00-like (IS/885) and IS/1494/06-like (IS/1494) in broiler chicks was investigated. Day-old chicks were separated into three groups, (I) vaccinated with H120 at day-old followed by CR88 at 14 days-old, (II) vaccinated with H120 and CR88 simultaneously at day-old and again with CR88 at 14 days-old, (III) control unvaccinated. At 30 days-old, each of the groups was challenged with virulent IS/885 or IS/1494. Protection was evaluated based on the clinical signs, tracheal and kidney gross lesions and tracheal ciliostasis. Results showed that administering combined live H120 and CR88 vaccines simultaneously at day-old followed by CR88 vaccine at 14 days-old gave more than 80 per cent tracheal ciliary protection from both of the Middle East isolates. In addition, this programme conferred 100 per cent protection from clinical signs and tracheal or kidney lesions. The other vaccination programme, H120 at day-old followed by CR88 at 14 days-old, the tracheal ciliary protection conferred were 60 per cent and 80 per cent from IS/885/00-like and IS/1494/06-like, respectively. PMID:26392909

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

    DTIC Science & Technology

    2012-11-26

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

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

    PubMed

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

    2015-04-01

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

  6. Vaccine-strain herpes zoster found in the trigeminal nerve area in a healthy child: A case report.

    PubMed

    Iwasaki, Sayaka; Motokura, Kouji; Honda, Yoshitaka; Mikami, Masamitsu; Hata, Daisuke; Hata, Atsuko

    2016-12-01

    A previously healthy 2-year-old girl, vaccinated for varicella at 17 months, was admitted because of left-sided facial herpes zoster caused by vaccine-strain varicella-zoster virus (VZV). She recovered fully with no complication after intravenous treatment using acyclovir. Earlier reports have described that herpes zoster (HZ) rashes caused by vaccine-strain VZV tend to occur on the dermis corresponding to the skin area where the varicella vaccine was received. However, rashes appeared on this girl only in the trigeminal nerve area, which is unrelated to the vaccinated site. Results underscore the importance of distinguishing vaccine-strain VZV from wild-type VZV whenever encountering HZ cases after vaccination, even in immunocompetent children, irrespective of the skin lesion site. Monitoring vaccine-strain HZ incidence rates is expected to elucidate many aspects of varicella vaccine safety.

  7. Complete Genome Sequences of Four Bordetella pertussis Vaccine Reference Strains from Serum Institute of India

    PubMed Central

    Peng, Yanhui; Loparev, Vladimir; Johnson, Taccara; Juieng, Phalasy; Gairola, Sunil; Kumar, Rakesh; Shaligram, Umesh; Gowrishankar, Ramnath; Moura, Hercules; Rees, Jon; Schieltz, David M.; Williamson, Yulanda; Woolfitt, Adrian; Barr, John; Tondella, M. Lucia; Williams, Margaret M.

    2016-01-01

    Serum Institute of India is among the world’s largest vaccine producers. Here, we report the complete genome sequences for four Bordetella pertussis strains used by Serum Institute of India in the production of whole-cell pertussis vaccines. PMID:28007855

  8. Experimental studies with homologous subtype vaccines produced with multiple antigenically different seed strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the high antigenic variability of avian influenza virus, vaccines need to be continually updated to maintain adequate protection to evolving field strains. One possible approach, to mitigating the effects of antigenic change, is to use vaccines containing more than one isolate of the same su...

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

    PubMed

    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.

  10. In vitro permissivity of bovine cells for wild-type and vaccinal myxoma virus strains.

    PubMed

    Pignolet, Béatrice; Duteyrat, Jean-Luc; Allemandou, Aude; Gelfi, Jacqueline; Foucras, Gilles; Bertagnoli, Stéphane

    2007-09-27

    Myxoma virus (MYXV), a leporide-specific poxvirus, represents an attractive candidate for the generation of safe, non-replicative vaccine vector for non-host species. However, there is very little information concerning infection of non-laboratory animals species cells with MYXV. In this study, we investigated interactions between bovine cells and respectively a wild type strain (T1) and a vaccinal strain (SG33) of MYXV. We showed that bovine KOP-R, BT and MDBK cell lines do not support MYXV production. Electron microscopy observations of BT-infected cells revealed the low efficiency of viral entry and the production of defective virions. In addition, infection of bovine peripheral blood mononuclear cells (PBMC) occurred at a very low level, even following non-specific activation, and was always abortive. We did not observe significant differences between the wild type strain and the vaccinal strain of MYXV, indicating that SG33 could be used for new bovine vaccination strategies.

  11. Genomic variations associated with attenuation in Mycobacterium avium subsp. paratuberculosis vaccine strains

    PubMed Central

    2013-01-01

    Background Mycobacterium avium subspecies paratuberculosis (MAP) whole cell vaccines have been widely used tools in the control of Johne’s disease in animals despite being unable to provide complete protection. Current vaccine strains derive from stocks created many decades ago; however their genotypes, underlying mechanisms and relative degree of their attenuation are largely unknown. Results Using mouse virulence studies we confirm that MAP vaccine strains 316 F, II and 2e have diverse but clearly attenuated survival and persistence characteristics compared with wild type strains. Using a pan genomic microarray we characterise the genomic variations in a panel of vaccine strains sourced from stocks spanning over 40 years of maintenance. We describe multiple genomic variations specific for individual vaccine stocks in both deletion (26–32 Kbp) and tandem duplicated (11–40 Kbp) large variable genomic islands and insertion sequence copy numbers. We show individual differences suitable for diagnostic differentiation between vaccine and wild type genotypes and provide evidence for functionality of some of the deleted MAP-specific genes and their possible relation to attenuation. Conclusions This study shows how culture environments have influenced MAP genome diversity resulting in large tandem genomic duplications, deletions and transposable element activity. In combination with classical selective systematic subculture this has led to fixation of specific MAP genomic alterations in some vaccine strain lineages which link the resulting attenuated phenotypes with deficiencies in high reactive oxygen species handling. PMID:23339684

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

    PubMed

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

    2014-08-01

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

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

    PubMed

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

    2015-01-01

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

  14. Comparison of a live attenuated Salmonella Enteritidis vaccine candidate secreting Escherichia coli heat-labile enterotoxin B subunit with a commercial vaccine for efficacy of protection against internal egg contamination by Salmonella in hens.

    PubMed

    Nandre, Rahul M; Eo, Seong Kug; Park, Sang Youel; Lee, John Hwa

    2015-07-01

    This study compared a new live attenuated Salmonella Enteritidis vaccine candidate secreting Escherichia coli heat-labile enterotoxin B subunit (SE-LTB) with a commercial Salmonella Enteritidis (SE) vaccine for efficacy of protection against SE infection in laying hens. Chickens were divided into 3 groups of 20 each. Group A chickens were inoculated orally with phosphate-buffered saline and served as controls, group B chickens were inoculated orally with the vaccine candidate, and group C chickens were inoculated intramuscularly with a commercial vaccine, the primary inoculation in groups B and C being at 10 wk of age and the booster at 16 wk. Groups B and C showed significantly higher titers of plasma immunoglobulin G, intestinal secretory immunoglobulin A, and egg yolk immunoglobulin Y antibodies compared with the control group, and both vaccinated groups showed a significantly elevated cellular immune response. After virulent challenge, group B had significantly lower production of thin-shelled and/or malformed eggs and a significantly lower rate of SE contamination of eggs compared with the control group. Furthermore, the challenge strain was detected significantly less in all of the examined organs of group B compared with the control group. Group C had lower gross lesion scores only in the spleen and had lower bacterial counts only in the spleen, ceca, and ovary. These findings indicate that vaccination with the SE-LTB vaccine candidate can efficiently reduce internal egg and internal organ contamination by Salmonella and has advantages over the commercial vaccine.

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

    PubMed Central

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

    2009-01-01

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

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

    PubMed

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

    2014-10-07

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

  17. The live attenuated dengue vaccine TV003 elicits complete protection against dengue in a human challenge model.

    PubMed

    Kirkpatrick, Beth D; Whitehead, Stephen S; Pierce, Kristen K; Tibery, Cecilia M; Grier, Palmtama L; Hynes, Noreen A; Larsson, Catherine J; Sabundayo, Beulah P; Talaat, Kawsar R; Janiak, Anna; Carmolli, Marya P; Luke, Catherine J; Diehl, Sean A; Durbin, Anna P

    2016-03-16

    A dengue human challenge model can be an important tool to identify candidate dengue vaccines that should be further evaluated in large efficacy trials in endemic areas. Dengue is responsible for about 390 million infections annually. Protective efficacy results for the most advanced dengue vaccine candidate (CYD) were disappointing despite its ability to induce neutralizing antibodies against all four dengue virus (DENV) serotypes. TV003 is a live attenuated tetravalent DENV vaccine currently in phase 2 evaluation. To better assess the protective efficacy of TV003, a randomized double-blind, placebo-controlled trial in which recipients of TV003 or placebo were challenged 6 months later with a DENV-2 strain, rDEN2Δ30, was conducted. The primary endpoint of the trial was protection against dengue infection, defined as rDEN2Δ30 viremia. Secondary endpoints were protection against rash and neutropenia. All 21 recipients of TV003 who were challenged with rDEN2Δ30 were protected from infection with rDEN2Δ30. None developed viremia, rash, or neutropenia after challenge. In contrast, 100% of the 20 placebo recipients who were challenged with rDEN2Δ30 developed viremia, 80% developed rash, and 20% developed neutropenia. TV003 induced complete protection against challenge with rDEN2Δ30 administered 6 months after vaccination. TV003 will be further evaluated in dengue-endemic areas. The controlled dengue human challenge model can accelerate vaccine development by evaluating the protection afforded by the vaccine, thereby eliminating poor candidates from further consideration before the initiation of large efficacy trials.

  18. Human transcriptome response to immunization with live-attenuated Venezuelan equine encephalitis virus vaccine (TC-83): Analysis of whole blood

    PubMed Central

    Erwin-Cohen, Rebecca A.; Porter, Aimee I.; Pittman, Phillip R.; Rossi, Cynthia A.; DaSilva, Luis

    2017-01-01

    ABSTRACT Venezuelan equine encephalitis virus (VEEV) is an important human and animal alphavirus pathogen transmitted by mosquitoes. The virus is endemic in Central and South America, but has also caused equine outbreaks in southwestern areas of the United States. In an effort to better understand the molecular mechanisms of the development of immunity to this important pathogen, we performed transcriptional analysis from whole, unfractionated human blood of patients who had been immunized with the live-attenuated vaccine strain of VEEV, TC-83. We compared changes in the transcriptome between naïve individuals who were mock vaccinated with saline to responses of individuals who received TC-83. Significant transcriptional changes were noted at days 2, 7, and 14 following vaccination. The top canonical pathways revealed at early and intermediate time points (days 2 and 7) included the involvement of the classic interferon response, interferon-response factors, activation of pattern recognition receptors, and engagement of the inflammasome. By day 14, the top canonical pathways included oxidative phosphorylation, the protein ubiquitination pathway, natural killer cell signaling, and B-cell development. Biomarkers were identified that differentiate between vaccinees and control subjects, at early, intermediate, and late stages of the development of immunity as well as markers which were common to all 3 stages following vaccination but distinct from the sham-vaccinated control subjects. The study represents a novel examination of molecular processes that lead to the development of immunity against VEEV in humans and which may be of value as diagnostic targets, to enhance modern vaccine design, or molecular correlates of protection. PMID:27870591

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

    PubMed

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

    2016-06-01

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

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

    PubMed

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

    1998-02-01

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

  1. An open‐label phase I trial of a live attenuated H2N2 influenza virus vaccine in healthy adults

    PubMed Central

    Talaat, Kawsar R.; Karron, Ruth A.; Liang, Philana H.; McMahon, Bridget A.; Luke, Catherine J.; Thumar, Bhagvanji; Chen, Grace L.; Min, Ji‐Young; Lamirande, Elaine W.; Jin, Hong; Coelingh, Kathy L.; Kemble, George W.; Subbarao, Kanta

    2012-01-01

    Please cite this paper as: Talaat et al. (2012) An open‐label phase I trial of a live attenuated H2N2 influenza virus vaccine in healthy adults. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00350.x. Background  Live attenuated influenza vaccines (LAIV) against a variety of strains of pandemic potential are being developed and tested. We describe the results of an open‐label phase I trial of a live attenuated H2N2 virus vaccine. Objectives  To evaluate the safety, infectivity, and immunogenicity of a live attenuated H2N2 influenza virus vaccine. Participants/methods  The A/Ann Arbor/6/60 (H2N2) virus used in this study is the attenuated, cold‐adapted, temperature‐sensitive strain that provides the genetic backbone of seasonal LAIV (MedImmune). We evaluated the safety, infectivity, and immunogenicity of two doses of 107 TCID50 of this vaccine administered by nasal spray 4 weeks apart to normal healthy seronegative adults. Results  Twenty‐one participants received a first dose of the vaccine; 18 participants received a second dose. No serious adverse events occurred during the trial. The most common adverse events after vaccination were headache and musculoskeletal pain. The vaccine was restricted in replication: 24% and 17% had virus detectable by culture or rRT‐PCR after the first and second dose, respectively. Antibody responses to the vaccine were also restricted: 24% of participants developed an antibody response as measured by either hemagglutination‐inhibition assay (10%), or ELISA for H2 HA‐specific serum IgG (24%) or IgA (16%) after either one or two doses. None of the participants had a neutralizing antibody response. Vaccine‐specific IgG‐secreting cells as measured by enzyme‐linked immunospot increased from a mean of 0·5 to 2·0/106 peripheral blood mononuclear cells (PBMCs); vaccine‐specific IgA‐secreting cells increased from 0·1 to 0·5/106 PBMCs. Conclusions  The live attenuated H2N2

  2. 9 CFR 113.67 - Erysipelothrix Rhusiopathiae Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Erysipelothrix Rhusiopathiae Vaccine... REQUIREMENTS Live Bacterial Vaccines § 113.67 Erysipelothrix Rhusiopathiae Vaccine. Erysipelothrix Rhusiopathiae Vaccine shall be prepared as a desiccated live culture of an avirulent or modified strain...

  3. 9 CFR 113.67 - Erysipelothrix Rhusiopathiae Vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Erysipelothrix Rhusiopathiae Vaccine... REQUIREMENTS Live Bacterial Vaccines § 113.67 Erysipelothrix Rhusiopathiae Vaccine. Erysipelothrix Rhusiopathiae Vaccine shall be prepared as a desiccated live culture of an avirulent or modified strain...

  4. 9 CFR 113.67 - Erysipelothrix Rhusiopathiae Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Erysipelothrix Rhusiopathiae Vaccine... REQUIREMENTS Live Bacterial Vaccines § 113.67 Erysipelothrix Rhusiopathiae Vaccine. Erysipelothrix Rhusiopathiae Vaccine shall be prepared as a desiccated live culture of an avirulent or modified strain...

  5. 9 CFR 113.67 - Erysipelothrix Rhusiopathiae Vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Erysipelothrix Rhusiopathiae Vaccine... REQUIREMENTS Live Bacterial Vaccines § 113.67 Erysipelothrix Rhusiopathiae Vaccine. Erysipelothrix Rhusiopathiae Vaccine shall be prepared as a desiccated live culture of an avirulent or modified strain...

  6. 9 CFR 113.67 - Erysipelothrix Rhusiopathiae Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Erysipelothrix Rhusiopathiae Vaccine... REQUIREMENTS Live Bacterial Vaccines § 113.67 Erysipelothrix Rhusiopathiae Vaccine. Erysipelothrix Rhusiopathiae Vaccine shall be prepared as a desiccated live culture of an avirulent or modified strain...

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

    PubMed

    Levenbook, Inessa

    2011-01-01

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

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

    PubMed

    Whitehead, Stephen S

    2016-01-01

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

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

    PubMed

    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.

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

    PubMed

    Herzog, Christian

    2016-01-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

    Hayami, Masanori; Horiuchi, Reii

    2004-06-01

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

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

    PubMed

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

    2013-09-01

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

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

    PubMed

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

    2004-12-01

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

  15. A Review of OIE Country Status Recovery Using Vaccinate-to-Live Versus Vaccinate-to-Die Foot-and-Mouth Disease Response Policies I: Benefits of Higher Potency Vaccines and Associated NSP DIVA Test Systems in Post-Outbreak Surveillance.

    PubMed

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

    2015-08-01

    To rapidly return to trade, countries with OIE status, FMD-free country where vaccination is not practised, have destroyed emergency vaccinated animals, raising ethical concerns with respect to social values, the environment, animal welfare and global food security. This two-part review explores whether science could support eligibility to return to previous OIE status in 3 months irrespective of vaccinate-to-live or vaccinate-to-die policies. Here, we examine the benefits of higher potency (≥ 6 PD50 ), high-purity vaccines formulated from antigen banks for emergency use, their efficacy and performance in differentiating infected from vaccinated animals (DIVA) assays for post-outbreak surveillance. From an intensive programme of research, we conclude that high-quality, higher potency vaccines are proven to reduce FMD virus (FMDV) subclinical circulation and the risk of carriers. Broader coverage than predicted by serology suggests the potential to hold a few 'key' vaccine strains improving logistics and reducing the financial burden of antigen banks. The OIE should adopt formal definitions for emergency vaccination and emergency vaccines. In terms of supportive tools, we consider that the lack of OIE recognition of DIVA tests other than those of PANAFTOSA in cattle is a shortcoming. There is need for research on maternal antibody interference with DIVA tests and on the use of such tests to establish whether greater purification of vaccines improves performance. We consider that alignment of waiting periods for vaccinate-to-live and vaccinate-to-die in OIE Code Article 8.5.9 1 b. and c. is feasible until an acceptable level of statistical certainty for surveillance or target probability of freedom is established to substantiate the absence of FMDV infection or circulation. It is surveillance intensity rather than waiting periods that establishes the risk of residual FMDV. EU Directive 2003/85/EC implicitly recognizes this, permitting derogation of the OIE waiting

  16. Evaluation of an attenuated strain of Ehrlichia canis as a vaccine for canine monocytic ehrlichiosis.

    PubMed

    Rudoler, Nir; Baneth, Gad; Eyal, Osnat; van Straten, Michael; Harrus, Shimon

    2012-12-17

    Canine monocytic ehrlichiosis is an important tick-borne disease worldwide. No commercial vaccine for the disease is currently available and tick control is the main preventive measure against the disease. The aim of this study was to evaluate the potential of a multi-passaged attenuated strain of Ehrlichia canis to serve as a vaccine for canine monocytic ehrlichiosis, and to assess the use of azithromycin in the treatment of acute ehrlichiosis. Twelve beagle dogs were divided into 3 groups of 4 dogs. Groups 1 and 2 were inoculated (vaccinated) with an attenuated strain of E. canis (#611A) twice or once, respectively. The third group consisted of naïve dogs which served as controls. All 3 groups were challenged with a wild virulent strain of E. canis by administering infected dog-blood intravenously. Transient thrombocytopenia was the only hematological abnormality observed following inoculation of dogs with the attenuated strain. Challenge with the virulent strain resulted in severe disease in all 4 control dogs while only 3 of 8 vaccinated dogs presented mild transient fever. Furthermore, the mean blood rickettsial load was significantly higher in the control group (27-92-folds higher during days 14-19 post challenge with the wild the strain) as compared to the vaccinated dogs. The use of azithromycin was assessed as a therapeutic agent for the acute disease. Four days treatment resulted in further deterioration of the clinical condition of the dogs. Molecular comparison of 4 genes known to express immunoreactive proteins and virulence factors (p30, gp19, VirB4 and VirB9) between the attenuated strain and the challenge wild strain revealed no genetic differences between the strains. The results of this study indicate that the attenuated E. canis strain may serve as an effective and secure future vaccine for canine ehrlichiosis.

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

    PubMed

    Issa, Mohammad Nouh; Ashhab, Yaqoub

    2016-09-22

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

  18. A test of antigenicity for the selection of strains for inclusion in cholera vaccines

    PubMed Central

    Finkelstein, Richard A.; Pongpairojana, Smarn

    1968-01-01

    The antigenicity of a large number of cholera vibrio strains was compared, in groups of rabbits, by evaluating the serological responses to single limited doses of vaccines prepared from the strains. On the basis of these tests, it was possible to construct 2 quadrivalent (El Tor and classical, Inaba and Ogawa) vaccines which differed significantly in antigenicity for rabbits but which were indistinguishable in the “standard” mouse-protection test. The advisability of using a test of antigenicity for selection of strains and laboratory evaluation of vaccines is considered. Application of the proposed antigenicity test would depend on further comparisons of human response to vaccines which differ in antigenicity for the rabbit. ImagesFIG. 4 PMID:5303406

  19. Rapid real-time PCR methods to distinguish Salmonella Enteritidis wildtype field isolates from vaccine strains Salmovac SE/Gallivac SE and AviPro SALMONELLA VAC E.

    PubMed

    Maurischat, Sven; Szabo, Istvan; Baumann, Beatrice; Malorny, Burkhard

    2015-05-01

    Salmonella enterica serovar Enteritidis is a major non-typhoid Salmonella serovar causing human salmonellosis mainly associated with the consumption of poultry and products thereof. To reduce infections in poultry, S. Enteritidis live vaccine strains AviPro SALMONELLA VAC E and Salmovac SE/Gallivac SE have been licensed and used in several countries worldwide. To definitively diagnose a S. Enteritidis contamination in vaccinated herds a reliable and fast method for the differentiation between vaccine and wildtype field isolates is required. In this study, we developed and validated real-time PCR (qPCR) assays to distinguish those variants genetically. Suitable target sequences were identified by whole genome sequencing (WGS) using the Illumina MiSeq system. SNP regions in kdpA and nhaA proved to be most useful for differentiation of AviPro SALMONELLA VAC E and Salmovac SE/Gallivac SE, respectively, from wildtype strains. For each vaccine strain one TaqMan-qPCR assay and one alternative approach using High Resolution Melting (HRM) analysis was designed. All 30 Salmovac SE and 7 AviPro SALMONELLA VAC E vaccine strain reisolates tested were correctly identified by both approaches (100% inclusivity). Furthermore, all 137 (TaqMan) and 97 (HRM) Salmonella non-vaccine and related Enterobacteriaceae strains tested were excluded (100% exclusivity). The analytical detection limits were determined to be approx. 10(2) genome copies/reaction for the TaqMan and 10(4) genome copies/reaction for the HRM approach. The real-time PCR assays proved to be a reliable and fast alternative to the cultural vaccine strain identification tests helping decision makers in control measurements to take action within a shorter period of time.

  20. Potential of a sequence-based antigenic distance measure to indicate equine influenza vaccine strain efficacy.

    PubMed

    Daly, Janet M; Elton, Debra

    2013-12-09

    The calculation of p(epitope) values, a sequence-based measure of antigenic distance between strains, was developed for human influenza. The potential to apply the p(epitope) value to equine influenza vaccine strain selection was assessed. There was a negative correlation between p(epitope) value and vaccine efficacy for pairs of vaccine and challenge strains used in cross-protection studies in ponies that just reached statistical significance (p=0.046) only if one pair of viruses was excluded from the analysis. Thus the p(epitope) value has potential to provide additional data to consider in the decision-making process for updating equine influenza vaccine strains. However, further work is required to define the epitopes of the equine H3N8 haemagglutinin protein recognised by equine antibodies, which could lead to refinement of the p(epitope) value calculation. Furthermore, other factors such as vaccine potency and virulence of circulating strains may also influence vaccine efficacy.

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

    PubMed Central

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

    2011-01-01

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

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

    PubMed

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

    2011-05-12

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

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

    USGS Publications Warehouse

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

    2004-01-01

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

  4. Computational prediction of vaccine strains for human influenza A (H3N2) viruses.

    PubMed

    Steinbrück, L; Klingen, T R; McHardy, A C

    2014-10-01

    Human influenza A viruses are rapidly evolving pathogens that cause substantial morbidity and mortality in seasonal epidemics around the globe. To ensure continued protection, the strains used for the production of the seasonal influenza vaccine have to be regularly updated, which involves data collection and analysis by numerous experts worldwide. Computer-guided analysis is becoming increasingly important in this problem due to the vast amounts of generated data. We here describe a computational method for selecting a suitable strain for production of the human influenza A virus vaccine. It interprets available antigenic and genomic sequence data based on measures of antigenic novelty and rate of propagation of the viral strains throughout the population. For viral isolates sampled between 2002 and 2007, we used this method to predict the antigenic evolution of the H3N2 viruses in retrospective testing scenarios. When seasons were scored as true or false predictions, our method returned six true positives, three false negatives, eight true negatives, and one false positive, or 78% accuracy overall. In comparison to the recommendations by the WHO, we identified the correct antigenic variant once at the same time and twice one season ahead. Even though it cannot be ruled out that practical reasons such as lack of a sufficiently well-growing candidate strain may in some cases have prevented recommendation of the best-matching strain by the WHO, our computational decision procedure allows quantitative interpretation of the growing amounts of data and may help to match the vaccine better to predominating strains in seasonal influenza epidemics. Importance: Human influenza A viruses continuously change antigenically to circumvent the immune protection evoked by vaccination or previously circulating viral strains. To maintain vaccine protection and thereby reduce the mortality and morbidity caused by infections, regular updates of the vaccine strains are required. We

  5. Protection and Long-Lived Immunity Induced by the ID93/GLA-SE Vaccine Candidate against a Clinical Mycobacterium tuberculosis Isolate.

    PubMed

    Baldwin, Susan L; Reese, Valerie A; Huang, Po-Wei D; Beebe, Elyse A; Podell, Brendan K; Reed, Steven G; Coler, Rhea N

    2015-12-09

    Mycobacterium tuberculosis HN878 represents a virulent clinical strain from the W-Beijing family, which has been tested in small animal models in order to study its virulence and its induction of host immune responses following infection. This isolate causes death and extensive lung pathology in infected C57BL/6 mice, whereas lab-adapted strains, such as M. tuberculosis H37Rv, do not. The use of this clinically relevant isolate of M. tuberculosis increases the possibilities of assessing the long-lived efficacy of tuberculosis vaccines in a relatively inexpensive small animal model. This model will also allow for the use of knockout mouse strains to critically examine key immunological factors responsible for long-lived, vaccine-induced immunity in addition to vaccine-mediated prevention of pulmonary immunopathology. In this study, we show that the ID93/glucopyranosyl lipid adjuvant (GLA)-stable emulsion (SE) tuberculosis vaccine candidate, currently in human clinical trials, is able to elicit protection against M. tuberculosis HN878 by reducing the bacterial burden in the lung and spleen and by preventing the extensive lung pathology induced by this pathogen in C57BL/6 mice.

  6. Randomized placebo controlled human volunteer trial of a live oral cholera vaccine VA1.3 for safety and immune response.

    PubMed

    Mahalanabis, D; Ramamurthy, T; Nair, G B; Ghosh, A; Shaikh, S; Sen, B; Thungapathra, M; Ghosh, R K; Pazhani, G P; Nandy, R K; Jana, S; Bhattacharya, S K

    2009-07-30

    A live oral cholera vaccine developed from a non-toxigenic Vibrio cholerae O1 El Tor strain VA1.3 was tested in a double-blind randomized placebo controlled study for safety and immunogenicity in 304 men aged between 16 and 50 years from Kolkata, India. A dose of 5 x 10(9)CFU (n=186) or a placebo (n=116) containing the diluent buffer was administered. The vaccine did not elicit adverse events except in two vaccine recipients with mild diarrhoea and vomiting. None excreted the vaccine strain. Vibriocidal antibody response developed in 105/186 (57%) and 5/116 (4%) in vaccine and placebo recipients, respectively. In a subgroup, anti-CT antibody rose (> or =2-folds) in 23/30 (77%) and 6/19 (32%) in vaccine and placebo recipients, respectively. These studies demonstrate that VA1.3 at a dose of 5 x 10(9) is safe and immunogenic in adults from a cholera endemic region.

  7. Draft Genome Sequence of Hypervirulent and Vaccine Candidate Streptococcus suis Strain SC19

    PubMed Central

    Teng, Lin; Dong, Xingxing; Zhou, Yang; Li, Zhiwei; Deng, Limei; Chen, Huanchun; Wang, Xiaohong

    2017-01-01

    ABSTRACT Streptococcus suis, a zoonotic bacterium found primarily in pigs, has been recognized recently as an emerging pathogen of humans. Herein, we describe the genome of Streptococcus suis strain SC19, a hypervirulent and vaccine candidate strain isolated from a pig amid the 2005 outbreak in China. PMID:28104658

  8. Complete Genome Sequence of the Attenuated Novobiocin-Resistant Streptococcus iniae Vaccine Strain ISNO

    PubMed Central

    Zhang, Dunhua; Zhang, Lee

    2014-01-01

    Streptococcus iniae ISNO is an attenuated novobiocin-resistant vaccine strain. Its full genome is 2,070,182 bp in length. The availability of this genome will allow comparative genomics to identify potential virulence genes important for pathogenesis of S. iniae and potential mechanisms associated with novobiocin resistance in this strain. PMID:24874684

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

    PubMed Central

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

    2003-01-01

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

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

    PubMed

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

    2009-11-05

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

  11. Alternative live-attenuated influenza vaccines based on modifications in the polymerase genes protect against epidemic and pandemic flu.

    PubMed

    Solórzano, Alicia; Ye, Jianqiang; Pérez, Daniel R

    2010-05-01

    Human influenza is a seasonal disease associated with significant morbidity and mortality. Influenza vaccination is the most effective means for disease prevention. We have previously shown that mutations in the PB1 and PB2 genes of the live-attenuated influenza vaccine (LAIV) from the cold-adapted (ca) influenza virus A/Ann Arbor/6/60 (H2N2) could be transferred to avian influenza viruses and produce partially attenuated viruses. We also demonstrated that avian influenza viruses carrying the PB1 and PB2 mutations could be further attenuated by stably introducing a hemagglutinin (HA) epitope tag in the PB1 gene. In this work, we wanted to determine whether these modifications would also result in attenuation of a so-called triple reassortant (TR) swine influenza virus (SIV). Thus, the TR influenza A/swine/Wisconsin/14094/99 (H3N2) virus was generated by reverse genetics and subsequently mutated in the PB1 and PB2 genes. Here we show that a combination of mutations in this TR backbone results in an attenuated virus in vitro and in vivo. Furthermore, we show the potential of our TR backbone as a vaccine that provides protection against the 2009 swine-origin pandemic influenza H1N1 virus (S-OIV) when carrying the surface of a classical swine strain. We propose that the availability of alternative backbones to the conventional ca A/Ann Arbor/6/60 LAIV strain could also be useful in epidemic and pandemic influenza and should be considered for influenza vaccine development. In addition, our data provide evidence that the use of these alternative backbones could potentially circumvent the effects of original antigenic sin (OAS) in certain circumstances.

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

    PubMed

    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.

  13. Evaluation of European tick-borne encephalitis virus vaccine against recent Siberian and far-eastern subtype strains.

    PubMed

    Hayasaka, D; Goto, A; Yoshii, K; Mizutani, T; Kariwa, H; Takashima, I

    2001-09-14

    To evaluate the efficacy of the European TBE vaccine in east-Siberian and far-eastern regions of Russia, we examined the immune responses of the vaccine against recent TBE virus Siberian (Irkutsk) and far-eastern (Khabarovsk and Vladivostok) isolates. The sera of vaccinated humans showed efficient neutralizing antibody titers (> or =20) against Siberian and far-eastern strains. To evaluate the efficacy of the vaccine in vivo, mice were vaccinated and challenged with lethal doses of the viruses. All vaccinated mice survived each virus challenge. These results suggest that the European vaccine can prevent the TBE virus infection in east-Siberian and far-eastern regions of Russia.

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

    PubMed

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

    2017-02-14

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2016-03-18

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

  17. Genotypic diversity in Babesia bovis field isolates and vaccine strains from South Africa.

    PubMed

    Combrink, M P; Troskie, P C; Pienaar, R; Latif, A A; Mans, B J

    2014-01-31

    Genotypic diversity in Babesia bovis (cause of Asiatic redwater in cattle) vaccine strains and field isolates from South Africa were investigated using the Bv80 gene as well as microsatellites. The S11 vaccine strain possessed both A and B alleles of the Bv80 gene, as well as genotypic diversity within each allele type as defined by repeat variation resulting in different amplicon sizes. Rapid serial passage of vaccine strain from passage S10 to S24 resulted in loss of genotypic diversity that yielded a single allele A genotype with an amplicon size of 558 bp. This suggested that clonal selection occurred during rapid passaging. Extensive genotypic diversity exists in 44 field isolates characterized with both Bv80 A and B alleles, but can be readily distinguished from the S24 vaccine strain using either the Bv80 allele specific PCR assays or using multi-locus micro-satellite typing. This indicated that no recent documented clinical cases of Asiatic redwater were caused by the reversion to virulence of the current vaccine strain.

  18. Adaptation of a Chinese ferret badger strain of rabies virus to high-titered growth in BHK-21 cells for canine vaccine development.

    PubMed

    Liu, Ye; Zhang, Shoufeng; Zhang, Fei; Hu, Rongliang

    2012-12-01

    Rabies virus strain JX08-45CC was derived from a Chinese isolate (JX08-45) by serial passage in the BHK-21 cell line, reaching a titer of 10(8) TCID(50)/mL. JX08-45CC produced rabies in adult mice but was nonpathogenic in dogs after intramuscular injection. A comparison of the entire genomes of JX08-45 and JX08-45CC led to the identification of 17 nucleotide substitutions, resulting in seven amino acid changes in the mature G and L proteins. The immunogenicity of β-propiolactone-inactivated JX08-45CC was similar to the immunogenicity of the live vaccine strains widely used in China. The inactivated vaccine induced antibody responses for more than 6 months and provided full protection from an intramuscular challenge in dogs. JX08-45CC has excellent potential for development as an inactivated vaccine for dogs in China.

  19. A Novel Live Pichinde Virus-Based Vaccine Vector Induces Enhanced Humoral and Cellular Immunity after a Booster Dose

    PubMed Central

    Dhanwani, Rekha; Zhou, Yanqin; Huang, Qinfeng; Verma, Vikram; Dileepan, Mythili; Ly, Hinh

    2015-01-01

    ABSTRACT Pichinde virus (PICV) is a bisegmented enveloped RNA virus that targets macrophages and dendritic cells (DCs) early in infection and induces strong innate and adaptive immunity in mice. We have developed a reverse genetics system to produce live recombinant PICV (strain P18) with a trisegmented RNA genome (rP18tri), which encodes all four PICV gene products and as many as two foreign genes. We have engineered the vector to express the green fluorescent protein (GFP) reporter gene (abbreviated as G in virus designations) and either the hemagglutination (HA [H]) or the nucleoprotein (NP [P]) gene of the influenza A/PR8 virus. The trisegmented viruses rP18tri-G/H and rP18tri-G/P showed slightly reduced growth in vitro and expressed HA and NP, respectively. Mice immunized with rP18tri-G/H were completely protected against lethal influenza virus challenge even 120 days after immunization. These rP18tri-based vectors could efficiently induce both neutralizing antibodies and antigen-specific T cell responses via different immunization routes. Interestingly, the immune responses were significantly increased upon a booster dose and remained at high levels even after three booster doses. In summary, we have developed a novel PICV-based live vaccine vector that can express foreign antigens to induce strong humoral and cell-mediated immunity and is ideal for a prime-and-boost vaccination strategy. IMPORTANCE We have developed a novel Pichinde virus (PICV)-based live viral vector, rP18tri, that packages three RNA segments and encodes as many as two foreign genes. Using the influenza virus HA and NP genes as model antigens, we show that this rP18tri vector can induce strong humoral and cellular immunity via different immunization routes and can lead to protection in mice. Interestingly, a booster dose further enhances the immune responses, a feature that distinguishes this from other known live viral vectors. In summary, our study demonstrates a unique feature of this

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

    DTIC Science & Technology

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  2. Modifications in the polymerase genes of a swine-like triple-reassortant influenza virus to generate live attenuated vaccines against 2009 pandemic H1N1 viruses.

    PubMed

    Pena, Lindomar; Vincent, Amy L; Ye, Jianqiang; Ciacci-Zanella, Janice R; Angel, Matthew; Lorusso, Alessio; Gauger, Philip C; Janke, Bruce H; Loving, Crystal L; Perez, Daniel R

    2011-01-01

    On 11 June 2009, the World Health Organization (WHO) declared that the outbreaks caused by novel swine-origin influenza A (H1N1) virus had reached pandemic proportions. The pandemic H1N1 (H1N1pdm) virus is the predominant influenza virus strain in the human population. It has also crossed the species barriers and infected turkeys and swine in several countries. Thus, the development of a vaccine that is effective in multiple animal species is urgently needed. We have previously demonstrated that the introduction of temperature-sensitive mutations into the PB2 and PB1 genes of an avian H9N2 virus, combined with the insertion of a hemagglutinin (HA) tag in PB1, resulted in an attenuated (att) vaccine backbone for both chickens and mice. Because the new pandemic strain is a triple-reassortant (TR) virus, we chose to introduce the double attenuating modifications into a swine-like TR virus isolate, A/turkey/OH/313053/04 (H3N2) (ty/04), with the goal of producing live attenuated influenza vaccines (LAIV). This genetically modified backbone had impaired polymerase activity and restricted virus growth at elevated temperatures. In vivo characterization of two H1N1 vaccine candidates generated using the ty/04 att backbone demonstrated that this vaccine is highly attenuated in mice, as indicated by the absence of signs of disease, limited replication, and minimum histopathological alterations in the respiratory tract. A single immunization with the ty/04 att-based vaccines conferred complete protection against a lethal H1N1pdm virus infection in mice. More importantly, vaccination of pigs with a ty/04 att-H1N1 vaccine candidate resulted in sterilizing immunity upon an aggressive intratracheal challenge with the 2009 H1N1 pandemic virus. Our studies highlight the safety of the ty/04 att vaccine platform and its potential as a master donor strain for the generation of live attenuated vaccines for humans and livestock.

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

    PubMed

    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.

  4. Strain-specific protective immunity following vaccination against experimental Trypanosoma cruzi infection.

    PubMed

    Haolla, Filipe A; Claser, Carla; de Alencar, Bruna C G; Tzelepis, Fanny; de Vasconcelos, José Ronnie; de Oliveira, Gabriel; Silvério, Jaline C; Machado, Alexandre V; Lannes-Vieira, Joseli; Bruna-Romero, Oscar; Gazzinelli, Ricardo T; dos Santos, Ricardo Ribeiro; Soares, Milena B P; Rodrigues, Mauricio M

    2009-09-18

    Immunisation with Amastigote Surface Protein 2 (asp-2) and trans-sialidase (ts) genes induces protective immunity in highly susceptible A/Sn mice, against infection with parasites of the Y strain of Trypanosoma cruzi. Based on immunological and biological strain variations in T. cruzi parasites, our goal was to validate our vaccination results using different parasite strains. Due to the importance of the CD8(+) T cells in protective immunity, we initially determined which strains expressed the immunodominant H-2K(k)-restricted epitope TEWETGQI. We tested eight strains, four of which elicited immune responses to this epitope (Y, G, Colombian and Colombia). We selected the Colombian and Colombia strains for our studies. A/Sn mice were immunised with different regimens using both T. cruzi genes (asp-2 and ts) simultaneously and subsequently challenged with blood trypomastigotes. Immune responses before the challenge were confirmed by the presence of specific antibodies and peptide-specific T cells. Genetic vaccination did not confer protective immunity against acute infection with a lethal dose of the Colombian strain. In contrast, we observed a drastic reduction in parasitemia and a significant increase in survival, following challenge with an otherwise lethal dose of the Colombia strain. In many surviving animals with late-stage chronic infection, we observed alterations in the heart's electrical conductivity, compared to naive mice. In summary, we concluded that immunity against T. cruzi antigens, similar to viruses and bacteria, may be strain-specific and have a negative impact on vaccine development.

  5. Comparative analysis of the Rotarix™ vaccine strain and G1P[8] rotaviruses detected before and after vaccine introduction in Belgium

    PubMed Central

    Heylen, Elisabeth; Tamim, Sana; McAllen, John K.; Kirkness, Ewen F.; Akopov, Asmik; De Coster, Sarah; Van Ranst, Marc; Matthijnssens, Jelle

    2017-01-01

    G1P[8] rotaviruses are responsible for the majority of human rotavirus infections worldwide. The effect of universal mass vaccination with rotavirus vaccines on circulating G1P[8] rotaviruses is still poorly understood. Therefore we analyzed the complete genomes of the Rotarix™ vaccine strain, and 70 G1P[8] rotaviruses, detected between 1999 and 2010 in Belgium (36 before and 34 after vaccine introduction) to investigate the impact of rotavirus vaccine introduction on circulating G1P[8] strains. All rotaviruses possessed a complete Wa-like genotype constellation, but frequent intra-genogroup reassortments were observed as well as multiple different cluster constellations circulating in a single season. In addition, identical cluster constellations were found to circulate persistently over multiple seasons. The Rotarix™ vaccine strain possessed a unique cluster constellation that was not present in currently circulating G1P[8] strains. At the nucleotide level, the VP6, VP2 and NSP2 gene segments of Rotarix™ were relatively distantly related to any Belgian G1P[8] strain, but other gene segments of Rotarix™ were found in clusters also containing circulating Belgian strains. At the amino acid level, the genetic distance between Rotarix™ and circulating Belgian strains was considerably lower, except for NSP1. When we compared the Belgian G1P[8] strains collected before and after vaccine introduction a reduction in the proportion of strains that were found in the same cluster as the Rotarix™ vaccine strain was observed for most gene segments. The reduction in the proportion of strains belonging to the same cluster may be the result of the vaccine introduction, although natural fluctuations cannot be ruled out. PMID:28070453

  6. Comparative analysis of the Rotarix™ vaccine strain and G1P[8] rotaviruses detected before and after vaccine introduction in Belgium.

    PubMed

    Zeller, Mark; Heylen, Elisabeth; Tamim, Sana; McAllen, John K; Kirkness, Ewen F; Akopov, Asmik; De Coster, Sarah; Van Ranst, Marc; Matthijnssens, Jelle

    2017-01-01

    G1P[8] rotaviruses are responsible for the majority of human rotavirus infections worldwide. The effect of universal mass vaccination with rotavirus vaccines on circulating G1P[8] rotaviruses is still poorly understood. Therefore we analyzed the complete genomes of the Rotarix™ vaccine strain, and 70 G1P[8] rotaviruses, detected between 1999 and 2010 in Belgium (36 before and 34 after vaccine introduction) to investigate the impact of rotavirus vaccine introduction on circulating G1P[8] strains. All rotaviruses possessed a complete Wa-like genotype constellation, but frequent intra-genogroup reassortments were observed as well as multiple different cluster constellations circulating in a single season. In addition, identical cluster constellations were found to circulate persistently over multiple seasons. The Rotarix™ vaccine strain possessed a unique cluster constellation that was not present in currently circulating G1P[8] strains. At the nucleotide level, the VP6, VP2 and NSP2 gene segments of Rotarix™ were relatively distantly related to any Belgian G1P[8] strain, but other gene segments of Rotarix™ were found in clusters also containing circulating Belgian strains. At the amino acid level, the genetic distance between Rotarix™ and circulating Belgian strains was considerably lower, except for NSP1. When we compared the Belgian G1P[8] strains collected before and after vaccine introduction a reduction in the proportion of strains that were found in the same cluster as the Rotarix™ vaccine strain was observed for most gene segments. The reduction in the proportion of strains belonging to the same cluster may be the result of the vaccine introduction, although natural fluctuations cannot be ruled out.

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

    PubMed

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

    2010-11-01

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

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

    PubMed

    Olsen, S C; Johnson, C

    2012-05-01

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

    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

  11. Development of a genotype specific live Newcastle disease vaccine by replacing the fusion (F) and hemagglutinin-neuramindase (HN) genes into a LaSota vaccine backbone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All Newcastle disease viruses (NDVs) are part of a single serotype; however, current vaccine strains display between 15 and 18% amino acid differences at the F and HN protein compared with current virulent viruses. Previous studies have shown that increased amino acid similarity between NDV vaccine...

  12. [Production of a vaccine against enterotoxemia from Clostridium perfringens strains isolated in the field].

    PubMed

    Cherfaoui, S; Kadra, B

    1992-01-01

    We have isolated eight strains of C. perfringens from cases of enterotoxaemia. Five of these strains have revealed themselves toxic with respective types (type "A":2, type "C":2, type "D":1). In order to produce anti-enterotoxaemia vaccine, we have proceeded at the cultivation in fermenter of isolated strains and reference strains CWA 35, CWC and CWD AF. At the end of fermentation, we have evaluated the two following parameters: obtained biomass, and toxin titers. With the two classes of strains we reached an important biomass but toxins titers relatively weak comparatively to that which is usually required. It will be necessary then, to demonstrate the immunogen value of the produced vaccines by testing their efficacity.

  13. Live Recombinant Salmonella Typhi Vaccines Constructed to Investigate the Role of rpoS in Eliciting Immunity to a Heterologous Antigen

    PubMed Central

    Brenneman, Karen E.; Wanda, Soo-Young; Wang, Shifeng; Senechal, Patti; Sun, Wei; Roland, Kenneth L.; Curtiss, Roy

    2010-01-01

    We hypothesized that the immunogenicity of live Salmonella enterica serovar Typhi vaccines expressing heterologous antigens depends, at least in part, on its rpoS status. As part of our project to develop a recombinant attenuated S. Typhi vaccine (RASTyV) to prevent pneumococcal diseases in infants and children, we constructed three RASTyV strains synthesizing the Streptococcus pneumoniae surface protein PspA to test this hypothesis. Each vector strain carried ten engineered mutations designed to optimize safety and immunogenicity. Two S. Typhi vector strains (χ9639 and χ9640) were derived from the rpoS mutant strain Ty2 and one (χ9633) from the RpoS+ strain ISP1820. In χ9640, the nonfunctional rpoS gene was replaced with the functional rpoS gene from ISP1820. Plasmid pYA4088, encoding a secreted form of PspA, was moved into the three vector strains. The resulting RASTyV strains were evaluated for safety in vitro and for immunogenicity in mice. All three RASTyV strains were similar to the live attenuated typhoid vaccine Ty21a in their ability to survive in human blood and human monocytes. They were more sensitive to complement and were less able to survive and persist in sewage and surface water than their wild-type counterparts. Adult mice intranasally immunized with any of the RASTyV strains developed immune responses against PspA and Salmonella antigens. The RpoS+ vaccines induced a balanced Th1/Th2 immune response while the RpoS− strain χ9639(pYA4088) induced a strong Th2 immune response. Immunization with any RASTyV provided protection against S. pneumoniae challenge; the RpoS+ strain χ9640(pYA4088) provided significantly greater protection than the ISP1820 derivative, χ9633(pYA4088). In the pre-clinical setting, these strains exhibited a desirable balance between safety and immunogenicity and are currently being evaluated in a Phase 1 clinical trial to determine which of the three RASTyVs has the optimal safety and immunogenicity profile in human

  14. Inactivation of SAM-methyltransferase is the mechanism of attenuation of a historic louse borne typhus vaccine strain.

    PubMed

    Liu, Yan; Wu, Bin; Weinstock, George; Walker, David H; Yu, Xue-Jie

    2014-01-01

    Louse borne typhus (also called epidemic typhus) was one of man's major scourges, and epidemics of the disease can be reignited when social, economic, or political systems are disrupted. The fear of a bioterrorist attack using the etiologic agent of typhus, Rickettsia prowazekii, was a reality. An attenuated typhus vaccine, R. prowazekii Madrid E strain, was observed to revert to virulence as demonstrated by isolation of the virulent revertant Evir strain from animals which were inoculated with Madrid E strain. The mechanism of the mutation in R. prowazekii that affects the virulence of the vaccine was not known. We sequenced the genome of the virulent revertant Evir strain and compared its genome sequence with the genome sequences of its parental strain, Madrid E. We found that only a single nucleotide in the entire genome was different between the vaccine strain Madrid E and its virulent revertant strain Evir. The mutation is a single nucleotide insertion in the methyltransferase gene (also known as PR028) in the vaccine strain that inactivated the gene. We also confirmed that the vaccine strain E did not cause fever in guinea pigs and the virulent revertant strain Evir caused fever in guinea pigs. We concluded that a single nucleotide insertion in the methyltransferase gene of R. prowazekii attenuated the R. prowazekii vaccine strain E. This suggested that an irreversible insertion or deletion mutation in the methyl transferase gene of R. prowazekii is required for Madrid E to be considered a safe vaccine.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Hepatitis C genotype 1 mosaic vaccines are immunogenic in mice and induce stronger T-cell responses than natural strains.

    PubMed

    Yusim, Karina; Dilan, Rebecca; Borducchi, Erica; Stanley, Kelly; Giorgi, Elena; Fischer, William; Theiler, James; Marcotrigiano, Joseph; Korber, Bette; Barouch, Dan H

    2013-02-01

    Despite improved hepatitis C virus (HCV) treatments, vaccines remain an effective and economic option for curtailing the epidemic. Mosaic protein HCV genotype 1 vaccine candidates designed to address HCV diversity were immunogenic in mice. They elicited stronger T-cell responses to NS3-NS4a and E1-E2 proteins than did natural strains, as assessed with vaccine-matched peptides.

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

    PubMed

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

    2016-12-12

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

  18. Erysipelothrix rhusiopathiae: genetic characterization of midwest US isolates and live commercial vaccines using pulsed-field gel electrophoresis.

    PubMed

    Opriessnig, T; Hoffman, L J; Harris, D L; Gaul, S B; Halbur, P G

    2004-03-01

    This is the first report of molecular characterization of US erysipelas field isolates and vaccine strains of Erysipelothrix rhusiopathiae by pulsed-field gel electrophoresis (PFGE). Erysipelas in pigs is mainly caused by E. rhusiopathiae serotypes 1a, 1b, and 2. In 2001, erysipelas reemerged as a clinical problem in pigs in the midwestern United States. In this work 90 erysipelas isolates (58 recent and 28 archived field isolates as well as 4 live-vaccine strains) were genetically characterized. Because of the limited availability of antiserum, 74/90 isolates (44/58 recent isolates) were serotyped. The serotype of the majority (79.6%) of the 44 recent isolates tested was determined to be 1a, 13.6% were serotype 1b, and 6.8% of recent isolates were serologically untypeable. Among all 90 isolates, 23 different PFGE patterns were identified. There were 43 isolates identified as serotype 1a with 4 genetic patterns: 38/43, 1A(I); 3/43, 1A(III); 1/43, 1B(V); and 1/43, 3B. Sixteen serotype 1b isolates had 11 unique genetic patterns: 4/16 were genotype 1B(III), 2/16 were genotype 3A(I), and 1/16 was in genotype groups 1A(V), 1A(VI), 1A(VII), 1B(I), 1B(IV), 1B(VII), 2, 4, and 5. Six genetic patterns were distinguished among the 10 serotype 2 isolates: 1A(IV) (1/10), 1A(V) (1/10), 1B(VI) (1/10), 2 (4/10), 7 (1/10), and 8 (2/8). Erysipelas vaccine strains (modified live) were similar to each other but different from current field strains, sharing 78.6% identity with the most prevalent genotype 1A(I) based on the PFGE-SmaI pattern. Compared with serotyping, PFGE genotyping is a more distinguishing technique, easy to perform and not dependent on the limited availability of antiserum.

  19. Immunogenicity and protective efficacy of cold-adapted X-31 live attenuated pre-pandemic H5N1 influenza vaccines.

    PubMed

    Jang, Yo Han; Jung, Eun-Ju; Byun, Young Ho; Lee, Kwang-Hee; Lee, Eun-Young; Lee, Yoon Jae; Seong, Baik Lin

    2013-07-18

    Despite global efforts to control influenza viruses, they have taken a heavy toll on human public health worldwide. Among particular threats is highly pathogenic avian H5N1 influenza virus (HPAI) due to not only its high mortality in humans but also possible human-to-human transmission either through reassortment with other human influenza viruses such as 2009 pandemic H1N1 influenza virus, or by genetic mutations. With the aim of developing effective vaccines against the H5N1 viruses, we generated two live attenuated H5N1 vaccine candidates against A/Indonesia/05/2005 (clade 2.1) and A/chicken/Korea/ES/2003 (clade 2.5) strains, in the genetic background of the cold-adapted donor strain of X-31. In mice, a single dose of immunization with each of the two vaccines was highly immunogenic inducing high titers of serum viral-neutralizing and hemagglutinin-inhibiting antibodies against the homologous H5N1 strain. Furthermore, significant levels of cross-clade antibody responses were induced by the vaccines, suggesting a broad-spectrum cross-reactivity against the heterologous H5N1 strains. The immunizations provided solid protections against heterologous lethal challenges with H5N2 virus, significantly reducing the morbidity and challenge virus replications in the respiratory tracts. The robustness of the antibody responses against both the homologous and heterologous strains, together with efficient protection against the lethal H5N2 challenge, strongly support the protection against wild type H5N1 infections. These results could serve as an experimental basis for the development of safe and effective H5N1 pre-pandemic vaccines while further addressing the biosecurity concerns associated with H5N1 HPAI.

  20. Safety, dose, immunogenicity, and transmissibility of an oral live attenuated Shigella flexneri 2a vaccine candidate (SC602) among healthy adults and school children in Matlab, Bangladesh.

    PubMed

    Rahman, Kazi Mizanur; Arifeen, Shams El; Zaman, K; Rahman, Mahbubur; Raqib, Rubhana; Yunus, Mohammad; Begum, Nazma; Islam, Md Shaheenul; Sohel, Badrul Munir; Rahman, Muntasirur; Venkatesan, Malabi; Hale, Thomas L; Isenbarger, Daniel W; Sansonetti, Philippe J; Black, Robert E; Baqui, Abdullah H

    2011-02-01

    In double-blind trials in Bangladesh, 88 adults, and 79 children (8-10 years) were randomized to receive either a single oral dose of 1 × 10(4), 1 × 10(5) or 1 × 10(6)CFU of SC602 (a live, attenuated Shigella flexneri 2a strain vaccine) or placebo. In the adult outpatient 1 × 10(6) CFU group, severe joint pain and body aches were reported by one and two vaccinees respectively. In the adult inpatient trial, SC602 was isolated from 3 volunteers, pre-vaccination antibody titers were high, and fourfold increases in serum IgG anti-LPS responses were observed in 2 of 5 subjects of the 1 × 10(6)CFU group. None of the volunteers developed diarrhea. Overall, SC602 was found to be associated with minimal vaccine shedding, minimal reactogenicity, no transmission risk, and low immune stimulation.

  1. Construction of a Streptococcus agalactiae phoB mutant and evaluation of its potential as an attenuated modified live vaccine in golden pompano, Trachinotus ovatus.

    PubMed

    Cai, Xiaohui; Wang, Bei; Peng, Yinhui; Li, Yuan; Lu, Yishan; Huang, Yucong; Jian, Jichang; Wu, Zaohe

    2016-11-21

    Streptococcus agalactiae is a Gram-positive pathogen that can survive inside professional phagocytes and nonphagocytic cells to cause septicemia and meningoencephalitis in freshwater and marine fish. However, vaccines based on extracellular products (ECP) and formalin-killed whole S. agalactiae cells, as well as subunit vaccine are unable to protect fish from infection by variant serotypes S. agalactiae. The search for live attenuated vaccine with highly conserved and virulent-related genes is essential for producing a vaccine to help understand and control streptococcosis In this study, the phoB gene was cloned from pathogenic S. agalactiae TOS01 strain and the mutant strain SAΔphoB was constructed via allelic exchange mutagenesis. The results showed that the deduced amino acid of S. agalactiae TOS01 shares high similarities with other Streptococcus spp. and has high conserved response regulator receiver domain (REC) and DNA-binding effector domain of two-component system response regulators (Trans_reg_C). Cell adherence and invasion assays, challenge experiments and histopathological changes post-vaccination were performed and observed, the results showed that the mutant strain SAΔphoB has a lower adherence and invasion rate and less virulent than the wild type strain in golden pompano, and it doesn't induce clinical symptoms and obvious pathological changes in golden pompano, thereby indicating that the deletion of phoB affects the virulence and infectious capacity of S. agalactiae. Golden pompano vaccinated via intraperitoneal injection SAΔphoB had the relative percent survival value of 93.1% after challenge with TOS01, demonstrating its high potential as an effective attenuated live vaccine candidate. Real-time PCR assays showed that the SAΔphoB was able to enhance the expression of immune-related genes, including MHC-I, MyD88, IL-22 and IL-10 after vaccination, indicating that the SAΔphoB is able to induce humoral and cell-mediated immune response in

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

    PubMed

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

    1997-01-01

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

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

    PubMed

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

    2002-02-01

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

  4. Development of bioluminescence imaging of respiratory syncytial virus (RSV) in virus-infected live mice and its use for evaluation of therapeutics and vaccines.

    PubMed

    Fuentes, Sandra; Arenas, Diego; Moore, Martin M; Golding, Hana; Khurana, Surender

    2017-01-23

    Respiratory Syncytial virus (RSV) is one of the leading causes of pneumonia among infants with no human vaccine or efficient curative treatments. Efforts are underway to develop new RSV vaccines and therapeutics. There is a dire need for animal models for preclinical evaluation and selection of products against RSV. Herein, we developed a whole body bioluminescence imaging to follow replication of RSV A2 virus strain expressing firefly luciferase (RSVA2-line19-FFL) in live BALB/c mice that can be used as an extremely sensitive readout for studying effects of antiviral and vaccines in living mice. Strong bioluminescence signal was detected in the nasal cavity and in the lungs following intranasal infection of mice with RSVA2-line19-FFL. The kinetics of viral replication in lungs quantified by daily live imaging strongly correlated with viral titers measured by ex-vivo plaque assay and by assessing viral RNA by qRT-PCR. Vaccination of mice with a pre-fusion F protein elicited high neutralizing antibody titers conferring strong protective immunity against virus replication in the nasal cavity and lungs. In contrast, post-challenge treatment of mice with the monoclonal antibody Palivizumab two days after infection reduced viral replication in the nasal cavity at day 4, but only modestly reduced virus loads in the lungs by day 5. In contrast to RSV bioluminescence, plaque assay did not detect viral titers in lungs on day 5 in Palivizumab-treated animals. This difference between viral loads measured by the two assays was found to be due to coating of virions with the Palivizumab that blocked infection of target cells in vitro and shows importance of live imaging in evaluation of RSV therapeutics. This recombinant RSV based live imaging animal model is convenient and valuable tool that can be used to study host dissemination of RSV and evaluation of antiviral compounds and vaccines against RSV.

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

    PubMed

    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.

  6. Safety and protective efficacy of a spiC and crp deletion mutant of Salmonella gallinarum as a live attenuated vaccine for fowl typhoid.

    PubMed

    Cheng, Zhao; Yin, Junlei; Kang, Xilong; Geng, Shizhong; Hu, Maozhi; Pan, Zhiming; Jiao, Xinan

    2016-08-01

    With an aim to develop a safe, immunogenic fowl typhoid (FT) vaccine, the safety and efficacy of 1009ΔspiCΔcrp, a spiC and crp deletion mutant of Salmonella gallinarum, were evaluated in chickens. Three-day-old chickens were intramuscularly immunized with 1009ΔspiCΔcrp (1×10(7)CFU) and boosted 7days later (at 10-days old) with the same dose and via the same route (vaccinated group). The vaccinated group showed no clinical symptoms and no differences in body weight compared to the unvaccinated control group. 1009ΔspiCΔcrp bacteria colonized and persisted in the liver and spleen of vaccinated chickens for >14days, and significant specific humoral and cellular immune responses were induced. Vaccinated chickens were challenged with S. gallinarum strain SG9 at 21days post-immunization (24-day-old chickens), and efficient protection was observed based on the mortality and clinical symptoms, as compared to those in the control group. These results demonstrate that 1009ΔspiCΔcrp can be used as a live attenuated vaccine.

  7. Evaluation of the safety, immunogenicity and efficacy of three capripoxvirus vaccine strains against lumpy skin disease virus.

    PubMed

    Gari, Getachew; Abie, Getnet; Gizaw, Daniel; Wubete, Alehegn; Kidane, Membere; Asgedom, Hagos; Bayissa, Berecha; Ayelet, Gelagay; Oura, Christopher A L; Roger, Francois; Tuppurainen, Eeva S M

    2015-06-22

    The safety, immunogenicity and efficacy of three commercially available vaccines against lumpy skin disease (LSD) in cattle have been evaluated using a combination of vaccine challenge experiments and the monitoring of immune responses in vaccinated animals in the field. The three vaccines evaluated in the study included two locally produced (Ethiopian) vaccines (lumpy skin disease virus (LSDV) Neethling and Kenyan sheep and goat pox (KSGP) O-180 strain vaccines) and a Gorgan goat pox (GTP) vaccine manufactured by Jordan Bio-Industries Centre (JOVAC). The latter vaccine was evaluated for the first time in cattle against LSDV. The Ethiopian Neethling and KSGPO-180 vaccines failed to provide protection in cattle against LSDV, whereas the Gorgan GTP vaccine protected all the vaccinated calves from clinical signs of LSD. There was no significant difference in protective efficacy detected between two dosage levels (P=0.2, P=0.25, and P=0.1 for KSGP, Neethling and Gorgan vaccines, respectively). Additionally, the Gorgan GTP vaccinated cattle showed stronger levels of cellular immune responses measured using Delayed-Type Hypersensitivity (DTH) reactions at the vaccination site indicating higher levels of immunogenicity produced by the GTPV vaccine in cattle, as opposed to the other two vaccines. This study indicated, for the first time, that the Gorgan GTP vaccine can effectively protect cattle against LSDV and that the Neethling and KSGP O-180 vaccine were not protective. The results emphasise the need for molecular characterization of the Neethling and KSGP O-180 vaccine seed viruses used for vaccine production in Ethiopia. In addition, the potency and efficacy testing process of the Ethiopian LSD Neethling and KSGP O-180 vaccines should be re-evaluated.

  8. A Vero-cell-adapted vaccine donor strain of influenza A virus generated by serial passages.

    PubMed

    Hu, Weibin; Zhang, Hong; Han, Qinglin; Li, Li; Chen, Yixin; Xia, Ningshao; Chen, Ze; Shu, Yuelong; Xu, Ke; Sun, Bing

    2015-01-03

    A cell culture-based vaccine production system is preferred for the large-scale production of influenza vaccines and has advantages for generating vaccines against highly pathogenic influenza A viruses. Vero cells have been widely used in human vaccine manufacturing, and the safety of these cells has been well demonstrated. However, the most commonly used influenza-vaccine donor virus, A/Puerto Rico/8/1934 (PR8) virus, does not grow efficiently in Vero cells. Therefore, we adapted the PR8 virus to Vero cells by continuous passaging, and a high-growth strain was obtained after 20 passages. Sequence analysis and virological assays of the adapted strain revealed that mutations in four viral internal genes (NP, PB1, PA and NS1) were sufficient for adaptation. The recombinant virus harboring these mutations (PR8-4mut) displayed accelerated viral transport into the nucleus and increased RNP activity. Importantly, the PR8-4mut could serve as a backbone donor virus to support the growth of the H7N1, H9N2 and H5N1 avian viruses and the H1N1 and H3N2 human viruses in Vero cells without changing its pathogenicity in either chicken embryos or mice. Thus, our work describes the generation of a Vero-adapted, high-yield PR8-4mut virus that may serve as a promising candidate for an influenza-vaccine donor virus.

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

    PubMed Central

    Araújo, Adriano Fernando; de Oliveira, Gabriel; Vasconcelos, Juliana Fraga; Ersching, Jonatan; Dominguez, Mariana Ribeiro; Vasconcelos, José Ronnie; Machado, Alexandre Vieira; Gazzinelli, Ricardo Tostes; Bruna-Romero, Oscar; Soares, Milena Botelho; Rodrigues, Mauricio Martins

    2014-01-01

    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. PMID:25061263

  10. A placebo-controlled dose response study of the reactogenicity and immunogenicity of a live cold-recombinant influenza B virus vaccine in healthy volunteers.

    PubMed

    Ganzinger, U; Bachmayer, H; Liehl, E; Martindale, J J; Hamilton, F; Kuwert, E K

    1988-06-01

    A live cold-recombinant influenza B virus vaccine (RB77) was given intranasally in a placebo-controlled, double blind study to volunteers in dosages of 10(7.9) EID50/ml, 10(7.25) EID50/ml, 10(5.7) EID50/ml. The tolerability, safety, and immunogenicity of the vaccine were investigated. No revertant virus was found in nasal swabs taken after immunisation. Local reactions were mild and showed a significant increase over the placebo only in the highest dose group. Systemic reactions were not different from the placebo. A significant increase in haemagglutinin inhibition titre was found in the highest dose group against the immunising strain (RB77) and the two wild strains B/TEC and B/Sing.

  11. Bluetongue viruses based on modified-live vaccine serotype 6 with exchanged outer shell proteins confer full protection in sheep against virulent BTV8.

    PubMed

    van Gennip, René G P; van de Water, Sandra G P; Maris-Veldhuis, Mieke; van Rijn, Piet A

    2012-01-01

    Since 1998, Bluetongue virus (BTV)-serotypes 1, 2, 4, 9, and 16 have invaded European countries around the Mediterranean Basin. In 2006, a huge BT outbreak started after incursion of BTV serotype 8 (BTV8) in North-Western Europe. IN 2008, BTV6 and BTV11 were reported in the Netherlands and Germany, and in Belgium, respectively. In addition, Toggenburg orbivirus (TOV) was detected in 2008 in Swiss goats, which was recognized as a new serotype of BTV (BTV25). The (re-)emergency of BTV serotypes needs a rapid response to supply effective vaccines. Reverse genetics has been developed for BTV1 and more recently also for BTV6. This latter strain, BTV6/net08, is closely related to live-attenuated vaccine for serotype 6 as determined by full genome sequencing. Here, we used this strain as backbone and exchanged segment 2 and 6, respectively Seg-2 (VP2) and Seg-6 (VP5), for those of BTV serotype 1 and 8 using reverse genetics. These so-called 'serotyped' vaccine viruses, as mono-serotype and multi-serotype vaccine, were compared for their protective capacity in sheep. In general, all vaccinated animals developed a neutralizing antibody response against their respective serotype. After challenge at three weeks post vaccination with cell-passaged, virulent BTV8/net07 (BTV8/net07/e1/bhkp3) the vaccinated animals showed nearly no clinical reaction. Even more, challenge virus could not be detected, and seroconversion or boostering after challenge was negligible. These data demonstrate that all sheep were protected from a challenge with BTV8/net07, since sheep of the control group showed viremia, seroconversion and clinical signs that are specific for Bluetongue. The high level of cross-protection is discussed.

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

    PubMed

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

    2015-01-03

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

  13. Machupo Virus Expressing GPC of the Candid#1 Vaccine Strain of Junin Virus Is Highly Attenuated and Immunogenic

    PubMed Central

    Koma, Takaaki; Patterson, Michael; Huang, Cheng; Seregin, Alexey V.; Maharaj, Payal D.; Miller, Milagros; Smith, Jeanon N.; Walker, Aida G.; Hallam, Steven

    2015-01-01

    ABSTRACT Machupo virus (MACV) is the causative agent of Bolivian hemorrhagic fever. Our previous study demonstrated that a MACV strain with a single amino acid substitution (F438I) in the transmembrane domain of glycoprotein is attenuated but genetically unstable in mice. MACV is closely related to Junin virus (JUNV), the causative agent of Argentine hemorrhagic fever. Others and our group have identified the glycoprotein to be the major viral factor determining JUNV attenuation. In this study, we tested the compatibility of the glycoprotein of the Candid#1 live-attenuated vaccine strain of JUNV in MACV replication and its ability to attenuate MACV in vivo. Recombinant MACV with the Candid#1 glycoprotein (rMACV/Cd#1-GPC) exhibited growth properties similar to those of Candid#1 and was genetically stable in vitro. In a mouse model of lethal infection, rMACV/Cd#1-GPC was fully attenuated, more immunogenic than Candid#1, and fully protective against MACV infection. Therefore, the MACV strain expressing the glycoprotein of Candid#1 is safe, genetically stable, and highly protective against MACV infection in a mouse model. IMPORTANCE Currently, there are no FDA-approved vaccines and/or treatments for Bolivian hemorrhagic fever, which is a fatal human disease caused by MACV. The development of antiviral strategies to combat viral hemorrhagic fevers, including Bolivian hemorrhagic fever, is one of the top priorities of the Implementation Plan of the U.S. Department of Health and Human Services Public Health Emergency Medical Countermeasures Enterprise. Here, we demonstrate for the first time that MACV expressing glycoprotein of Candid#1 is a safe, genetically stable, highly immunogenic, and protective vaccine candidate against Bolivian hemorrhagic fever. PMID:26581982

  14. Choice of High-Efficacy Strains for the Annual Influenza Vaccine

    NASA Astrophysics Data System (ADS)

    Deem, Michael

    2005-03-01

    We introduce a model of protein evolution to explain limitations in the immune system response to vaccination and disease [1]. The phenomenon of original antigenic sin, wherein vaccination creates memory sequences that can increase susceptibility to future exposures to the same disease, is explained as stemming from localization of the immune system response in antibody sequence space. This localization is a result of the roughness in sequence space of the evolved antibody affinity constant for antigen and is observed for diseases with high year-to-year mutation rates, such as influenza. We show that the order parameter within this theory correlates well with efficacies of the H3N2 influenza A component of the annual vaccine between 1971 and 2004 [2,3]. This new measure of antigenic distance predicts vaccine efficacy significantly more accurately than do current state-of-the-art phylogenetic sequence analyses or ferret antisera inhibition assays. We discuss how this new measure of antigenic distance may be used in the context of annual influenza vaccine design and monitoring of vaccine efficacy. 1) M. W. Deem and H. Y. Lee, Phys. Rev. Lett. 91 (2003) 068101. 2) E. T. Munoz and M. W. Deem,q-bio.BM/0408016. 3) V. Gupta, D. J. Earl, and M. W. Deem, ``Choice of High-Efficacy Strains for the Annual Influenza Vaccine,'' submitted.

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

    PubMed

    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.

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

    PubMed

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

    2017-01-01

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

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

    PubMed Central

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

    2017-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  19. Draft Genome Sequence of the Vaccination Strain Mycobacterium bovis BCG S4-Jena

    PubMed Central

    Wibberg, Daniel; Winkler, Anika; Straube, Eberhard; Karrasch, Matthias; Keller, Peter M.

    2016-01-01

    Here, we present the draft genome sequence of Mycobacterium bovis BCG S4-Jena, a tuberculosis vaccine strain. The genome of S4-Jena is represented by 48 scaffolds, consisting of 132 scaffolded contigs and amounting to a size of about 4.2 Mb. New genes potentially encoding a phage fragment were identified in the genome. PMID:27103721

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

    Hughes, Austin L

    2009-09-01

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

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

    PubMed

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

    2016-01-01

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

  3. Evaluation of the Salmonella enterica Serovar Pullorum Pathogenicity Island 2 Mutant as a Candidate Live Attenuated Oral Vaccine

    PubMed Central

    Yin, Junlei; Cheng, Zhao; Wang, Xiaochun; Xu, Lijuan; Li, Qiuchun; Geng, Shizhong

    2015-01-01

    Salmonella enterica serovar Pullorum (S. Pullorum) is a highly adapted pathogen that causes pullorum disease (PD), an important systemic disease of poultry that causes severe economic losses in developing countries. In the interests of developing a safe and immunogenic oral vaccine, the efficacy of a Salmonella pathogenicity island 2 (SPI2)-deleted mutant of S. Pullorum (S06004ΔSPI2) was evaluated in chickens. S06004ΔSPI2 was severely less virulent than the parental wild-type strain S06004 as determined by the 50% lethal dose (LD50) for 3-day-old chickens when injected intramuscularly. Two-day-old chickens immunized with a single oral dose of S06004ΔSPI2 showed no differences in body weight or clinical symptoms compared with those in the negative-control group. S06004ΔSPI2 bacteria were not isolated from livers or spleens of immunized chickens after a short period of time, and specific humoral and cellular immune responses were significantly induced. Immunized chickens were challenged with S. Pullorum strain S06004 and Salmonella enterica serovar Gallinarum (S. Gallinarum) strain SG9 at 10 days postimmunization (dpi), and efficient protection against the challenges was observed. None of the immunized chickens died, the clinical symptoms were slight and temporary following challenge in immunized chickens compared with those in the control group, and these chickens recovered by 3 to 5 dpi. Overall, these results demonstrate that S06004ΔSPI2 can be used as a live attenuated oral vaccine. PMID:25924763

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

    PubMed

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

    2016-06-01

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

  5. 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.

    PubMed

    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.

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

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  8. Screening vaccine candidate strains against Streptococcus agalactiae of tilapia based on PFGE genotype.

    PubMed

    Chen, Ming; Wang, Rui; Li, Li-Ping; Liang, Wan-Wen; Li, Jian; Huang, Yan; Lei, Ai-Ying; Huang, Wei-Yi; Gan, Xi

    2012-09-14

    The immunogenicity identification of epidemic strain is important for the development and application of vaccine. In this study, 85 Streptococcus agalactiae prevalent strains from the tilapia main cultured areas of China were distributed among 10 distinct PFGE genotypes (A-J). For each genotype, one representative strain (S.a(A)-S.a(J)) was selected to develop an inactivated whole-cell bacterial vaccine (V(A)-V(J)), which then underwent a protective immunity test. V(A)-V(J) showed similar relative percent survival (RPS) to the homologous or heterologous strains with the identical genotype, while the average RPS among V(A)-V(J) protecting against itself genotype strains showed large differences (44.71-98.81%). The RPS of V(A)-V(J) vaccinated fish against infections by the mixture of S.a(A)-S.a(J) at 15 days post vaccination (dpv) was ranged from 13.33% to 60.00%, and V(B), V(D), V(F), and V(G) showed the highest RPS of 60.00%, 46.67%, 53.33% and 60.00% respectively. V(B), V(D) and V(G) have their own specific protection scope, V(B) showed strong protective immunity to infections caused by A-D, F, G and J (53.57-100%), and V(G) showed strong protective immunity to C-H and J (50.00-100%), whereas V(D) showed weak protective immunity to all non-self genotype strains (14.81-36.67%). The results of the combined vaccination showed that V(G)+V(B) group had wider protection scope and higher RPS value than V(G)+V(D) group. Our results demonstrated that the protective immunity of S. agalactiae from tilapia was not only associated with their serotypes, but also related to their PFGE genotypes. It is difficult to acquire a single vaccine candidate strain that can protect against all genotype strains from the same serotype.

  9. Development of one-step real-time PCR assay for titrating trivalent live attenuated influenza vaccines

    PubMed Central

    Zang, Yang; Du, Dongchuan; Ge, Peng; Xu, Yongqing; Liu, Xintao; Zhang, Yan; Su, Weiheng; Kiseleva, Irina; Rudenko, Larisa; Xu, Fei; Kong, Wei; Jiang, Chunlai

    2014-01-01

    Traditionally, infectivity of a trivalent live attenuated influenza vaccines (LAIVs) is titrated by determining the 50% egg infectious dose assay (EID50) or plaque forming units (PFU), which requires specific monoclonal antibodies to neutralize 2 strains while estimating the titer of the non-neutralized strain. Compared to this time-consuming, laborious, subjective and variable process, reverse transcription-quantitative real-time PCR (RT-qPCR) technology has advantages of rapidity, sensitivity, reproducibility and reduced contamination, thus has been applied widely for detecting pathogens and measuring viral titers. In this study, the critical harvest time was determined to be 18 h post-infection (hpi) for type A influenza and 12 hpi for type B influenza, but no significant difference between titers at 12 hpi and 18 hpi for the type B strain was observed. In conclusion, trivalent LAIVs can be titrated simultaneously within 24 h by this one-step RT-qPCR assay, which yielded titers comparable to those obtained by the traditional EID50 assay. Therefore, the RT-qPCR assay ma