Sample records for tb vaccine development

  1. Progress and challenges in TB vaccine development

    PubMed Central

    Voss, Gerald; Casimiro, Danilo; Neyrolles, Olivier; Williams, Ann; Kaufmann, Stefan H.E.; McShane, Helen; Hatherill, Mark; Fletcher, Helen A

    2018-01-01

    The Bacille Calmette Guerin (BCG) vaccine can provide decades of protection against tuberculosis (TB) disease, and although imperfect, BCG is proof that vaccine mediated protection against TB is a possibility. A new TB vaccine is, therefore, an inevitability; the question is how long will it take us to get there? We have made substantial progress in the development of vaccine platforms, in the identification of antigens and of immune correlates of risk of TB disease. We have also standardized animal models to enable head-to-head comparison and selection of candidate TB vaccines for further development.  To extend our understanding of the safety and immunogenicity of TB vaccines we have performed experimental medicine studies to explore route of administration and have begun to develop controlled human infection models. Driven by a desire to reduce the length and cost of human efficacy trials we have applied novel approaches to later stage clinical development, exploring alternative clinical endpoints to prevention of disease outcomes. Here, global leaders in TB vaccine development discuss the progress made and the challenges that remain. What emerges is that, despite scientific progress, few vaccine candidates have entered clinical trials in the last 5 years and few vaccines in clinical trials have progressed to efficacy trials. Crucially, we have undervalued the knowledge gained from our “failed” trials and fostered a culture of risk aversion that has limited new funding for clinical TB vaccine development. The unintended consequence of this abundance of caution is lack of diversity of new TB vaccine candidates and stagnation of the clinical pipeline. We have a variety of new vaccine platform technologies, mycobacterial antigens and animal and human models.  However, we will not encourage progression of vaccine candidates into clinical trials unless we evaluate and embrace risk in pursuit of vaccine development. PMID:29568497

  2. Progress and challenges in TB vaccine development.

    PubMed

    Voss, Gerald; Casimiro, Danilo; Neyrolles, Olivier; Williams, Ann; Kaufmann, Stefan H E; McShane, Helen; Hatherill, Mark; Fletcher, Helen A

    2018-01-01

    The Bacille Calmette Guerin (BCG) vaccine can provide decades of protection against tuberculosis (TB) disease, and although imperfect, BCG is proof that vaccine mediated protection against TB is a possibility. A new TB vaccine is, therefore, an inevitability; the question is how long will it take us to get there? We have made substantial progress in the development of vaccine platforms, in the identification of antigens and of immune correlates of risk of TB disease. We have also standardized animal models to enable head-to-head comparison and selection of candidate TB vaccines for further development.  To extend our understanding of the safety and immunogenicity of TB vaccines we have performed experimental medicine studies to explore route of administration and have begun to develop controlled human infection models. Driven by a desire to reduce the length and cost of human efficacy trials we have applied novel approaches to later stage clinical development, exploring alternative clinical endpoints to prevention of disease outcomes. Here, global leaders in TB vaccine development discuss the progress made and the challenges that remain. What emerges is that, despite scientific progress, few vaccine candidates have entered clinical trials in the last 5 years and few vaccines in clinical trials have progressed to efficacy trials. Crucially, we have undervalued the knowledge gained from our "failed" trials and fostered a culture of risk aversion that has limited new funding for clinical TB vaccine development. The unintended consequence of this abundance of caution is lack of diversity of new TB vaccine candidates and stagnation of the clinical pipeline. We have a variety of new vaccine platform technologies, mycobacterial antigens and animal and human models.  However, we will not encourage progression of vaccine candidates into clinical trials unless we evaluate and embrace risk in pursuit of vaccine development.

  3. Tuberculosis vaccine development at a divide.

    PubMed

    Kaufmann, Stefan H E

    2014-05-01

    Tuberculosis (TB) remains a major health threat that will only be defeated by a combination of better drugs, diagnostics and vaccines. The only licensed TB vaccine, bacille Calmette-Guérin (BCG), protects against extrapulmonary TB in infants. Novel vaccine candidates that could protect against pulmonary TB either in TB naïve or in latent TB-infected healthy individuals have been developed and are currently being assessed in clinical trials. Subunit booster vaccines are either based on viral vectors expressing TB-specific antigens or on TB-protein antigens in adjuvants. Subunit vaccines are administered on top of BCG. Replacement vaccines for BCG are recombinant viable BCG or Mycobacterium tuberculosis. Several candidates are undergoing, or will soon start, phase IIb assessment for efficacy. The first vaccine candidate, MVA85A, to complete a phase IIb trial, unfortunately failed to show protection against TB in infants. Therapeutic vaccines composed of killed mycobacterial preparations target patients with complicated TB in adjunct to drug treatment. With increasing numbers of TB vaccine candidates in clinical trials, financial, regulatory and infrastructural issues arise, which would be best tackled by a global strategy. In addition, selection of the most promising vaccine candidates for further clinical development gains increasing importance.

  4. Challenges and solutions for a rational vaccine design for TB-endemic regions.

    PubMed

    Gowthaman, Uthaman; Mushtaq, Khurram; Tan, Amabel C; Rai, Pradeep K; Jackson, David C; Agrewala, Javed N

    2015-01-01

    Vaccines have been successful for global eradication or control of dreaded diseases such as smallpox, diphtheria, tetanus, yellow fever, whooping cough, polio, and measles. Unfortunately, this success has not been achieved for controlling tuberculosis (TB) worldwide. Bacillus Calmette Guérin (BCG) is the only available vaccine against TB. Paradoxically, BCG has deciphered success in the Western world but has failed in TB-endemic areas. In this article, we highlight and discuss the aspects of immunity responsible for controlling Mycobacterium tuberculosis infection and factors responsible for the failure of BCG in TB-endemic countries. In addition, we also suggest strategies that contribute toward the development of successful vaccine in protecting populations where BCG has failed.

  5. Advocacy, partnership and political commitment for TB vaccine research.

    PubMed

    Olesen, Ole F; Chan, Sharon; Chappell, Janice; Guo, Yan; Leite, Luciana C C

    2016-08-01

    The 4th Global Forum on TB Vaccines, convened in Shanghai, China, from 21 - 24 April 2015, brought together a wide and diverse community involved in tuberculosis vaccine research and development to discuss the current status of, and future directions for this critical effort. This paper summarizes the sessions on Advancing the Pipeline: A Vision for the Next Decade, Engaging the BRICS: Basic Research to Manufacturing, and Regulatory and Access Issues for New TB Vaccines. Summaries of all sessions from the 4th Global Forum are compiled in a special supplement of Tuberculosis. [August 2016, Vol 99, Supp S1, S1-S30]. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Optimal Control for TB disease with vaccination assuming endogeneous reactivation and exogeneous reinfection

    NASA Astrophysics Data System (ADS)

    Anggriani, N.; Wicaksono, B. C.; Supriatna, A. K.

    2016-06-01

    Tuberculosis (TB) is one of the deadliest infectious disease in the world which caused by Mycobacterium tuberculosis. The disease is spread through the air via the droplets from the infectious persons when they are coughing. The World Health Organization (WHO) has paid a special attention to the TB by providing some solution, for example by providing BCG vaccine that prevent an infected person from becoming an active infectious TB. In this paper we develop a mathematical model of the spread of the TB which assumes endogeneous reactivation and exogeneous reinfection factors. We also assume that some of the susceptible population are vaccinated. Furthermore we investigate the optimal vaccination level for the disease.

  7. The current status, challenges, and future developments of new tuberculosis vaccines.

    PubMed

    Gong, Wenping; Liang, Yan; Wu, Xueqiong

    2018-03-30

    Mycobacterium tuberculosis complex causes tuberculosis (TB), one of the top 10 causes of death worldwide. TB results in more fatalities than multi-drug resistant (MDR) HIV strain related coinfection. Vaccines play a key role in the prevention and control of infectious diseases. Unfortunately, the only licensed preventive vaccine against TB, bacilli Calmette-Guérin (BCG), is ineffective for prevention of pulmonary TB in adults. Therefore, it is very important to develop novel vaccines for TB prevention and control. This literature review provides an overview of the innate and adaptive immune response during M. tuberculosis infection, and presents current developments and challenges to novel TB vaccines. A comprehensive understanding of vaccines in preclinical and clinical studies provides extensive insight for the development of safer and more efficient vaccines, and may inspire new ideas for TB prevention and treatment.

  8. Successes and failures in human tuberculosis vaccine development.

    PubMed

    Zenteno-Cuevas, Roberto

    2017-12-01

    Tuberculosis (TB) is an infectious disease caused mainly by Mycobacterium tuberculosis. In 2016, the WHO estimated 10.5 million new cases and 1.8 million deaths, making this disease the leading cause of death by an infectious agent. The current and projected TB situation necessitates the development of new vaccines with improved attributes compared to the traditional BCG method. Areas covered: In this review, the authors describe the most promising candidate vaccines against TB and discuss additional key elements in vaccine development, such as animal models, new adjuvants and immunization routes and new strategies for the identification of candidate vaccines. Expert opinion: At present, around 13 candidate vaccines for TB are in the clinical phase of evaluation; however, there is still no substitute for the BCG vaccine. One major impediment to developing an effective vaccine is our lack of understanding of several of the mechanisms associated with infection and the immune response against TB. However, the recent implementation of an entirely new set of technological advances will facilitate the proposal of new candidates. Finally, development of a new vaccine will require a major coordination of effort in order to achieve its effective administration to the people most in need of it.

  9. Review: New Vaccine Against Tuberculosis: Current Developments and Future Challenges

    NASA Astrophysics Data System (ADS)

    Liu, Jun

    2009-04-01

    Tuberculosis (TB) continues to be a global health threat. BCG was developed as an attenuated live vaccine for tuberculosis control nearly a century ago. Despite being the most widely used vaccine in human history, BCG is not an ideal vaccine and has two major limitations: its poor efficacy against adult pulmonary TB and its disconcerting safety in immunocompromised individuals. A safer and more effective TB vaccine is urgently needed. This review article discusses current strategies to develop the next generation of TB vaccines to replace BCG. While some progresses have been made in the past decade, significant challenges lie ahead.

  10. "The Impact of Mycobacterium tuberculosis Immune Evasion on Protective Immunity: Implications for TB Vaccine Design" - Meeting report.

    PubMed

    Boggiano, Cesar; Eichelberg, Katrin; Ramachandra, Lakshmi; Shea, Jaqueline; Ramakrishnan, Lalita; Behar, Samuel; Ernst, Joel D; Porcelli, Steven A; Maeurer, Markus; Kornfeld, Hardy

    2017-06-14

    Tuberculosis (TB) is the major cause of death from infectious diseases around the world, particularly in HIV infected individuals. TB vaccine design and development have been focused on improving Bacille Calmette-Guérin (BCG) and evaluating recombinant and viral vector expressed Mycobacterium tuberculosis (Mtb) proteins, for boosting BCG-primed immunity, but these approaches have not yet yielded significant improvements over the modest effects of BCG in protecting against infection or disease. On March 7-8, 2016, the National Institute of Allergy and Infectious Diseases (NIAID) convened a workshop on "The Impact of Mtb Immune Evasion on Protective Immunity: Implications for TB Vaccine Design" with the goal of defining immune mechanisms that could be targeted through novel research approaches, to inform vaccine design and immune therapeutic interventions for prevention of TB. The workshop addressed early infection events, the impact of Mtb evolution on the development and maintenance of an adaptive immune response, and the factors that influence protection against and progression to active disease. Scientific gaps and areas of study to revitalize and accelerate TB vaccine design were discussed and prioritized. These included a comprehensive evaluation of innate and Mtb-specific adaptive immune responses in the lung at different stages of disease; determining the role of B cells and antibodies (Abs) during Mtb infection; development of better assays to measure Mtb burden following exposure, infection, during latency and after treatment, and approaches to improving current animal models to study Mtb immunogenicity, TB disease and transmission. Copyright © 2017.

  11. Detection of circulating Mycobacterium tuberculosis-specific DNA by droplet digital PCR for vaccine evaluation in challenged monkeys and TB diagnosis.

    PubMed

    Song, Neng; Tan, Yang; Zhang, Lingyun; Luo, Wei; Guan, Qing; Yan, Ming-Zhe; Zuo, Ruiqi; Liu, Weixiang; Luo, Feng-Ling; Zhang, Xiao-Lian

    2018-04-24

    Mycobacterium tuberculosis (M. tb) is emerging as a more serious pathogen due to the increased multidrug-resistant TB and co-infection of human immunodeficiency virus (HIV). The development of an effective and sensitive detection method is urgently needed for bacterial load evaluation in vaccine development, early TB diagnosis, and TB treatment. Droplet digital polymerase chain reaction (ddPCR) is a newly developed sensitive PCR method for the absolute quantification of nucleic acid concentrations. Here, we used ddPCR to quantify the circulating virulent M. tb-specific CFP10 (10-kDa culture filtrate protein, Rv3874) and Rv1768 DNA copy numbers in the blood samples from Bacille Calmette-Guerin (BCG)-vaccinated and/or virulent M. tb H37Rv-challenged rhesus monkeys. We found that ddPCR was more sensitive compared to real-time fluorescence quantitative PCR (qPCR), as the detection limits of CFP10 were 1.2 copies/μl for ddPCR, but 15.8 copies/μl for qPCR. We demonstrated that ddPCR could detect CFP10 and Rv1768 DNA after 3 weeks of infection and at least two weeks earlier than qPCR in M.tb H37Rv-challenged rhesus monkey models. DdPCR could also successfully quantify CFP10 and Rv1768 DNA copy numbers in clinical TB patients' blood samples (active pulmonary TB, extrapulmonary TB (EPTB), and infant TB). To our knowledge, this study is the first to demonstrate that ddPCR is an effective and sensitive method of measuring the circulating CFP10 and Rv1768 DNA for vaccine development, bacterial load evaluation in vivo, and early TB (including EPTB and infant TB) diagnosis as well.

  12. Vaccines for Leprosy and Tuberculosis: Opportunities for Shared Research, Development, and Application

    PubMed Central

    Coppola, Mariateresa; van den Eeden, Susan J. F.; Robbins, Naoko; Wilson, Louis; Franken, Kees L. M. C.; Adams, Linda B.; Gillis, Tom P.; Ottenhoff, Tom H. M.; Geluk, Annemieke

    2018-01-01

    Tuberculosis (TB) and leprosy still represent significant public health challenges, especially in low- and lower middle-income countries. Both poverty-related mycobacterial diseases require better tools to improve disease control. For leprosy, there has been an increased emphasis on developing tools for improved detection of infection and early diagnosis of disease. For TB, there has been a similar emphasis on such diagnostic tests, while increased research efforts have also focused on the development of new vaccines. Bacille Calmette–Guérin (BCG), the only available TB vaccine, provides insufficient and inconsistent protection to pulmonary TB in adults. The impact of BCG on leprosy, however, is significant, and the introduction of new TB vaccines that might replace BCG could, therefore, have serious impact also on leprosy. Given the similarities in antigenic makeup between the pathogens Mycobacterium tuberculosis (Mtb) and M. leprae, it is well possible, however, that new TB vaccines could cross-protect against leprosy. New TB subunit vaccines currently evaluated in human phase I and II studies indeed often contain antigens with homologs in M. leprae. In this review, we discuss pre-clinical studies and clinical trials of subunit or whole mycobacterial vaccines for TB and leprosy and reflect on the development of vaccines that could provide protection against both diseases. Furthermore, we provide the first preclinical evidence of such cross-protection by Mtb antigen 85B (Ag85B)-early secretory antigenic target (ESAT6) fusion recombinant proteins in in vivo mouse models of Mtb and M. leprae infection. We propose that preclinical integration and harmonization of TB and leprosy research should be considered and included in global strategies with respect to cross-protective vaccine research and development. PMID:29535713

  13. Safety and immunogenicity of candidate vaccine M72/AS01E in adolescents in a TB endemic setting.

    PubMed

    Penn-Nicholson, Adam; Geldenhuys, Hennie; Burny, Wivine; van der Most, Robbert; Day, Cheryl L; Jongert, Erik; Moris, Philippe; Hatherill, Mark; Ofori-Anyinam, Opokua; Hanekom, Willem; Bollaerts, Anne; Demoitie, Marie-Ange; Kany Luabeya, Angelique Kany; De Ruymaeker, Evi; Tameris, Michele; Lapierre, Didier; Scriba, Thomas J

    2015-07-31

    Vaccination that prevents tuberculosis (TB) disease, particularly in adolescents, would have the greatest impact on the global TB epidemic. Safety, reactogenicity and immunogenicity of the vaccine candidate M72/AS01E was evaluated in healthy, HIV-negative adolescents in a TB endemic region, regardless of Mycobacterium tuberculosis (M.tb) infection status. In a phase II, double-blind randomized, controlled study (NCT00950612), two doses of M72/AS01E or placebo were administered intramuscularly, one month apart. Participants were followed-up post-vaccination, for 6 months. M72-specific immunogenicity was evaluated by intracellular cytokine staining analysis of T cells and NK cells by flow cytometry. No serious adverse events were recorded. M72/AS01E induced robust T cell and antibody responses, including antigen-dependent NK cell IFN-γ production. CD4 and CD8 T cell responses were sustained at 6 months post vaccination. Irrespective of M.tb infection status, vaccination induced a high frequency of M72-specific CD4 T cells expressing multiple combinations of Th1 cytokines, and low level IL-17. We observed rapid boosting of immune responses in M.tb-infected participants, suggesting natural infection acts as a prime to vaccination. The clinically acceptable safety and immunogenicity profile of M72/AS01E in adolescents living in an area with high TB burden support the move to efficacy trials. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Safety and immunogenicity of candidate vaccine M72/AS01E in adolescents in a TB endemic setting

    PubMed Central

    Penn-Nicholson, Adam; Geldenhuys, Hennie; Burny, Wivine; van der Most, Robbert; Day, Cheryl L.; Jongert, Erik; Moris, Philippe; Hatherill, Mark; Ofori-Anyinam, Opokua; Hanekom, Willem

    2018-01-01

    Background Vaccination that prevents tuberculosis (TB) disease, particularly in adolescents, would have the greatest impact on the global TB epidemic. Safety, reactogenicity and immunogenicity of the vaccine candidate M72/AS01E was evaluated in healthy, HIV-negative adolescents in a TB endemic region, regardless of Mycobacterium tuberculosis (M.tb) infection status. Methods In a phase II, double-blind randomized, controlled study (NCT00950612), two doses of M72/AS01E or placebo were administered intramuscularly, one month apart. Participants were followed-up post-vaccination, for 6 months. M72-specific immunogenicity was evaluated by intracellular cytokine staining analysis of T cells and NK cells by flow cytometry. Results No serious adverse events were recorded. M72/AS01E induced robust T cell and antibody responses, including antigen-dependent NK cell IFN-γ production. CD4 and CD8 T cell responses were sustained at 6 months post vaccination. Irrespective of M.tb infection status, vaccination induced a high frequency of M72-specific CD4 T cells expressing multiple combinations of Th1 cytokines, and low level IL-17. We observed rapid boosting of immune responses in M.tb-infected participants, suggesting natural infection acts as a prime to vaccination. Conclusions The clinically acceptable safety and immunogenicity profile of M72/AS01E in adolescents living in an area with high TB burden support the move to efficacy trials. PMID:26072017

  15. TBVAC2020: Advancing Tuberculosis Vaccines from Discovery to Clinical Development.

    PubMed

    Kaufmann, Stefan H E; Dockrell, Hazel M; Drager, Nick; Ho, Mei Mei; McShane, Helen; Neyrolles, Olivier; Ottenhoff, Tom H M; Patel, Brij; Roordink, Danielle; Spertini, François; Stenger, Steffen; Thole, Jelle; Verreck, Frank A W; Williams, Ann

    2017-01-01

    TBVAC2020 is a research project supported by the Horizon 2020 program of the European Commission (EC). It aims at the discovery and development of novel tuberculosis (TB) vaccines from preclinical research projects to early clinical assessment. The project builds on previous collaborations from 1998 onwards funded through the EC framework programs FP5, FP6, and FP7. It has succeeded in attracting new partners from outstanding laboratories from all over the world, now totaling 40 institutions. Next to the development of novel vaccines, TB biomarker development is also considered an important asset to facilitate rational vaccine selection and development. In addition, TBVAC2020 offers portfolio management that provides selection criteria for entry, gating, and priority settings of novel vaccines at an early developmental stage. The TBVAC2020 consortium coordinated by TBVI facilitates collaboration and early data sharing between partners with the common aim of working toward the development of an effective TB vaccine. Close links with funders and other consortia with shared interests further contribute to this goal.

  16. TBVAC2020: Advancing Tuberculosis Vaccines from Discovery to Clinical Development

    PubMed Central

    Kaufmann, Stefan H. E.; Dockrell, Hazel M.; Drager, Nick; Ho, Mei Mei; McShane, Helen; Neyrolles, Olivier; Ottenhoff, Tom H. M.; Patel, Brij; Roordink, Danielle; Spertini, François; Stenger, Steffen; Thole, Jelle; Verreck, Frank A. W.; Williams, Ann; Britton, Warwick

    2017-01-01

    TBVAC2020 is a research project supported by the Horizon 2020 program of the European Commission (EC). It aims at the discovery and development of novel tuberculosis (TB) vaccines from preclinical research projects to early clinical assessment. The project builds on previous collaborations from 1998 onwards funded through the EC framework programs FP5, FP6, and FP7. It has succeeded in attracting new partners from outstanding laboratories from all over the world, now totaling 40 institutions. Next to the development of novel vaccines, TB biomarker development is also considered an important asset to facilitate rational vaccine selection and development. In addition, TBVAC2020 offers portfolio management that provides selection criteria for entry, gating, and priority settings of novel vaccines at an early developmental stage. The TBVAC2020 consortium coordinated by TBVI facilitates collaboration and early data sharing between partners with the common aim of working toward the development of an effective TB vaccine. Close links with funders and other consortia with shared interests further contribute to this goal. PMID:29046674

  17. Status of vaccine research and development of vaccines for tuberculosis.

    PubMed

    Evans, Thomas G; Schrager, Lew; Thole, Jelle

    2016-06-03

    TB is now the single pathogen that causes the greatest mortality in the world, at over 1.6 million deaths each year. The widely used the 90 year old BCG vaccine appears to have minimal impact on the worldwide incidence despite some efficacy in infants. Novel vaccine development has accelerated in the past 15 years, with 15 candidates entering human trials; two vaccines are now in large-scale efficacy studies. Modeling by three groups has consistently shown that mass vaccination that includes activity in the latently infected population, especially adolescents and young adults, will likely have the largest impact on new disease transmission. At present the field requires better validated animal models, better understanding of a correlate of immunity, new cost-effective approaches to Proof of Concept trials, and increased appreciation by the public health and scientific community for the size of the problem and the need for a vaccine. Such a vaccine is likely to also play a role in the era of increasing antibiotic resistance. Ongoing efforts and studies are working to implement these needs over the next 5 years, which will lead to an understanding that will increase the likelihood of a successful TB vaccine. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  18. Tuberculosis vaccines in clinical trials

    PubMed Central

    Rowland, Rosalind; McShane, Helen

    2011-01-01

    Effective prophylactic and/or therapeutic vaccination is a key strategy for controlling the global TB epidemic. The partial effectiveness of the existing TB vaccine, bacille Calmette–Guérin (BCG), suggests effective vaccination is possible and highlights the need for an improved vaccination strategy. Clinical trials are evaluating both modifications to the existing BCG immunization methods and also novel TB vaccines, designed to replace or boost BCG. Candidate vaccines in clinical development include live mycobacterial vaccines designed to replace BCG, subunit vaccines designed to boost BCG and therapeutic vaccines designed as an adjunct to chemotherapy. There is a great need for validated animal models, identification of immunological biomarkers of protection and field sites with the capacity for large-scale efficacy testing in order to develop and license a novel TB vaccine or regimen. PMID:21604985

  19. Current status of new tuberculosis vaccine in children

    PubMed Central

    Pang, Yu; Zhao, Aihua; Cohen, Chad; Kang, Wanli; Lu, Jie; Wang, Guozhi; Zhao, Yanlin; Zheng, Suhua

    2016-01-01

    ABSTRACT Pediatric tuberculosis contributes significantly to the burden of TB disease worldwide. In order to achieve the goal of eliminating TB by 2050, an effective TB vaccine is urgently needed to prevent TB transmission in children. BCG vaccination can protect children from the severe types of TB such as TB meningitis and miliary TB, while its efficacy against pediatric pulmonary TB ranged from no protection to very high protection. In recent decades, multiple new vaccine candidates have been developed, and shown encouraging safety and immunogenicity in the preclinical experiments. However, the limited data on protective efficacy in infants evaluated by clinical trials has been disappointing, an example being MVA85A. To date, no vaccine has been shown to be clinically safer and more effective than the presently licensed BCG vaccine. Hence, before a new vaccine is developed with more promising efficacy, we must reconsider how to better use the current BCG vaccine to maximize its effectiveness in children. PMID:27002369

  20. Developing whole mycobacteria cell vaccines for tuberculosis: Workshop proceedings, Max Planck Institute for Infection Biology, Berlin, Germany, July 9, 2014.

    PubMed

    2015-06-12

    On July 9, 2014, Aeras and the Max Planck Institute for Infection Biology convened a workshop entitled "Whole Mycobacteria Cell Vaccines for Tuberculosis" at the Max Planck Institute for Infection Biology on the grounds of the Charité Hospital in Berlin, Germany, close to the laboratory where, in 1882, Robert Koch first identified Mycobacterium tuberculosis (Mtb) as the pathogen responsible for tuberculosis (TB). The purpose of the meeting was to discuss progress in the development of TB vaccines based on whole mycobacteria cells. Live whole cell TB vaccines discussed at this meeting were derived from Mtb itself, from Bacille Calmette-Guérin (BCG), the only licensed vaccine against TB, which was genetically modified to reduce pathogenicity and increase immunogenicity, or from commensal non-tuberculous mycobacteria. Inactivated whole cell TB and non-tuberculous mycobacterial vaccines, intended as immunotherapy or as safer immunization alternatives for HIV+ individuals, also were discussed. Workshop participants agreed that TB vaccine development is significantly hampered by imperfect animal models, unknown immune correlates of protection and the absence of a human challenge model. Although a more effective TB vaccine is needed to replace or enhance the limited effectiveness of BCG in all age groups, members of the workshop concurred that an effective vaccine would have the greatest impact on TB control when administered to adolescents and adults, and that use of whole mycobacteria cells as TB vaccine candidates merits greater support, particularly given the limited understanding of the specific Mtb antigens necessary to generate an immune response capable of preventing Mtb infection and/or disease. Copyright © 2015. Published by Elsevier Ltd.. All rights reserved.

  1. Tuberculosis Vaccines and Prevention of Infection

    PubMed Central

    Day, Tracey A.; Scriba, Thomas J.; Hatherill, Mark; Hanekom, Willem A.; Evans, Thomas G.; Churchyard, Gavin J.; Kublin, James G.; Bekker, Linda-Gail; Self, Steven G.

    2014-01-01

    SUMMARY Tuberculosis (TB) is a leading cause of death worldwide despite the availability of effective chemotherapy for over 60 years. Although Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccination protects against active TB disease in some populations, its efficacy is suboptimal. Development of an effective TB vaccine is a top global priority that has been hampered by an incomplete understanding of protective immunity to TB. Thus far, preventing TB disease, rather than infection, has been the primary target for vaccine development. Several areas of research highlight the importance of including preinfection vaccines in the development pipeline. First, epidemiology and mathematical modeling studies indicate that a preinfection vaccine would have a high population-level impact for control of TB disease. Second, immunology studies support the rationale for targeting prevention of infection, with evidence that host responses may be more effective during acute infection than during chronic infection. Third, natural history studies indicate that resistance to TB infection occurs in a small percentage of the population. Fourth, case-control studies of BCG indicate that it may provide protection from infection. Fifth, prevention-of-infection trials would have smaller sample sizes and a shorter duration than disease prevention trials and would enable opportunities to search for correlates of immunity as well as serve as a criterion for selecting a vaccine product for testing in a larger TB disease prevention trial. Together, these points support expanding the focus of TB vaccine development efforts to include prevention of infection as a primary goal along with vaccines or other interventions that reduce the rate of transmission and reactivation. PMID:25428938

  2. Tuberculosis vaccine development: strength lies in tenacity.

    PubMed

    Kaufmann, Stefan H E

    2012-07-01

    The past decade has witnessed a tremendous increase in the development of novel vaccines against tuberculosis (TB). In mice, each of these vaccine candidates stimulates an immune response that reduces the bacillary load, reflecting control but not sterilization of infection. Yet, the immune mechanisms underlying vaccine efficacy are only partially understood. In parallel to clinical assessment of current candidates, the next generation of vaccine candidates still needs to be developed. This requires basic research on how to induce the most efficacious immune response. Equally important is the dissection of immune responses in patients, latently infected healthy individuals, and participants of clinical vaccine trials. Amalgamation of this information will foster the way towards more efficacious vaccination strategies that not only prevent disease, but prevent or abolish infection. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Development and Initial Testing of Messages to Encourage Tuberculosis Testing and Treatment Among Bacille Calmette-Guerin (BCG) Vaccinated Persons

    PubMed Central

    Galindo-Gonzalez, Sebastian; Irani, Tracy A.

    2017-01-01

    Misperceptions surrounding the Bacille Calmette-Guerin (BCG) vaccine can lead some vaccinated individuals to resist being tested and treated for tuberculosis (TB). Educational messages to best explain the risk of TB to BCG-vaccinated, Hispanic persons were systematically developed and tested. First, TB program staff provided messages they considered effective. These were analyzed and validated by TB experts, and then presented in group interviews initially to foreign-born Hispanic persons with a TB diagnosis, and then persons without a prior TB diagnosis. Based on interviewees’ feedback, preferred statements were used to develop one long and three short comprehensive messages. One-on-one interviews were conducted with Hispanic persons to assess the saliency of the comprehensive educational messages. Participants preferred messages that were gain or positively-framed and explained that BCG does not confer lifelong protection against TB. Participants confirmed the messages would likely have a positive impact on patient decisions to undergo TB testing and treatment. PMID:24141428

  4. Vaccination against tuberculosis in badgers and cattle: an overview of the challenges, developments and current research priorities in Great Britain.

    PubMed

    Chambers, M A; Carter, S P; Wilson, G J; Jones, G; Brown, E; Hewinson, R G; Vordermeier, M

    2014-07-26

    Bovine tuberculosis (TB) is a significant threat to the cattle industry in England and Wales. It is widely acknowledged that a combination of measures targeting both cattle and wildlife will be required to eradicate bovine TB or reduce its prevalence until European official freedom status is achieved. Vaccination of cattle and/or badgers could contribute to bovine TB control in Great Britain, although there are significant gaps in our knowledge regarding the impact that vaccination would actually have on bovine TB incidence. Laboratory studies have demonstrated that vaccination with BCG can reduce the progression and severity of TB in both badgers and cattle. This is encouraging in terms of the prospect of a sustained vaccination programme achieving reductions in disease prevalence; however, developing vaccines for tackling the problem of bovine TB is challenging, time-consuming and resource-intensive, as this review article sets out to explain. British Veterinary Association.

  5. Perspectives for Developing New Tuberculosis Vaccines Derived from the Pathogenesis of Tuberculosis: I. Basic Principles, II. Preclinical Testing, and III. Clinical Testing

    PubMed Central

    Dannenberg, Arthur M.; Dey, Bappaditya

    2013-01-01

    Part I. Basic Principles. TB vaccines cannot prevent establishment of the infection. They can only prevent an early pulmonary tubercle from developing into clinical disease. A more effective new vaccine should optimize both cell-mediated immunity (CMI) and delayed-type hypersensitivity (DTH) better than any existing vaccine. The rabbit is the only laboratory animal in which all aspects of the human disease can be reproduced: namely, the prevention of most primary tubercles, the arrestment of most primary tubercles, the formation of the tubercle’s solid caseous center, the liquefaction of this center, the formation of cavities and the bronchial spread of the disease. In liquefied caseum, virulent tubercle bacilli can multiply extracellularly, especially in the liquefied caseum next to the inner wall of a cavity where oxygen is plentiful. The bacilli in liquefied caseum cannot be reached by the increased number of activated macrophages produced by TB vaccines. Therefore, new TB vaccines will have little or no effect on the extracellular bacillary growth within liquefied caseum. TB vaccines can only increase the host’s ability to stop the development of new TB lesions that arise from the bronchial spread of tubercle bacilli from the cavity to other parts of the lung. Therefore, effective TB vaccines do not prevent the reactivation of latent TB. Such vaccines only control (or reduce) the number of metastatic lesions that result after the primary TB lesion was reactivated by the liquefaction process. (Note: the large number of tubercle bacilli growing extracellularly in liquefied caseum gives rise to mutations that enable antimicrobial resistance—which is a major reason why TB still exists today). Part II. Preclinical Testing. The counting of grossly visible tubercles in the lungs of rabbits after the inhalation of virulent human-type tubercle bacilli is the most pertinent preclinical method to assess the efficacy of new TB vaccines (because an effective vaccine

  6. Accelerating Next Generation Vaccine Development for Global Disease Prevention

    PubMed Central

    Koff, Wayne C; Burton, Dennis R.; R.Johnson, Philip; Walker, Bruce D.; King, Charles R.; Nabel, Gary J.; Ahmed, Rafi; Bhan, Maharaj Kishan; Plotkin, Stanley A.

    2014-01-01

    Summary Vaccines are among the greatest successes in the history of public health. However, past strategies for vaccine development are unlikely to succeed in the future against major global diseases such as AIDS, TB, and malaria. For such diseases, the correlates of protection are poorly defined and the pathogens evade immune detection and/or exhibit extensive genetic variability. Recent advances have heralded in a new era of vaccine discovery. However, translation of these advances into vaccines remains impeded by lack of understanding of key vaccinology principles in humans. We review these advances towards vaccine discovery and suggest that for accelerating successful vaccine development, new human immunology-based clinical research initiatives be implemented with the goal of elucidating and more effectively inducing vaccine-induced protective immune responses. PMID:23723240

  7. What's new in tuberculosis vaccines?

    PubMed Central

    Ginsberg, Ann M.

    2002-01-01

    Over the past 10 years, tuberculosis (TB) vaccine development has resurged as an active area of investigation. The renewed interest has been stimulated by the recognition that, although BCG is delivered to approximately 90% of all neonates globally through the Expanded Programme on Immunization, Mycobacterium tuberculosis continues to cause over 8 million new cases of TB and over 2 million deaths annually. Over one hundred TB vaccine candidates have been developed, using different approaches to inducing protective immunity. Candidate vaccines are typically screened in small animal models of primary TB disease for their ability to protect against a virulent strain of M. tuberculosis. The most promising are now beginning to enter human safety trials, marking real progress in this field for the first time in 80 years. PMID:12132007

  8. TB & HIV: the deadly intersection.

    PubMed

    MacDougall, D S

    1999-05-01

    About 2 billion people worldwide are infected with Mycobacterium tuberculosis, the causative agent of tuberculosis (TB). TB is the leading cause of premature death in less industrialized countries, and 8 million more people become infected every year. The World Health Organization (WHO) declared TB a global emergency in 1993 and launched a series of prevention and vaccination programs. In spite of effective drug therapy and a vaccine, tuberculosis remains a major public health problem. The TB and HIV epidemics are closely intertwined, and the risk of TB disease progression is 100 times greater in HIV-positive individuals. TB is the leading cause of death among HIV-infected people worldwide, and virologic evidence suggests that the host immune response to TB may enhance HIV replication and accelerate the progression of HIV infection. The interaction between the two diseases was the subject of a conference called TB & HIV: Applying Advances to the Clinic, Public Health, and the World. Charts and tables show reported TB cases in the U.S., trends in TB cases among foreign-born persons in the U.S., and the country of origin for foreign-born persons with TB in the U.S. Several poster sessions from the conference are summarized. Strategies for dealing with the TB epidemic are outlined.

  9. Mucosal Vaccination against Tuberculosis Using Inert Bioparticles

    PubMed Central

    Reljic, Rajko; Sibley, Laura; Huang, Jen-Min; Pepponi, Ilaria; Hoppe, Andreas; Hong, Huynh A.

    2013-01-01

    Needle-free, mucosal immunization is a highly desirable strategy for vaccination against many pathogens, especially those entering through the respiratory mucosa, such as Mycobacterium tuberculosis. Unfortunately, mucosal vaccination against tuberculosis (TB) is impeded by a lack of suitable adjuvants and/or delivery platforms that could induce a protective immune response in humans. Here, we report on a novel biotechnological approach for mucosal vaccination against TB that overcomes some of the current limitations. This is achieved by coating protective TB antigens onto the surface of inert bacterial spores, which are then delivered to the respiratory tract. Our data showed that mice immunized nasally with coated spores developed humoral and cellular immune responses and multifunctional T cells and, most importantly, presented significantly reduced bacterial loads in their lungs and spleens following pathogenic challenge. We conclude that this new vaccine delivery platform merits further development as a mucosal vaccine for TB and possibly also other respiratory pathogens. PMID:23959722

  10. Evaluation of vaccines in the EU TB Vaccine Cluster using a guinea pig aerosol infection model of tuberculosis.

    PubMed

    Williams, Ann; Hatch, Graham J; Clark, Simon O; Gooch, Karen E; Hatch, Kim A; Hall, Graham A; Huygen, Kris; Ottenhoff, Tom H M; Franken, Kees L M C; Andersen, Peter; Doherty, T Mark; Kaufmann, Stefan H E; Grode, Leander; Seiler, Peter; Martin, Carlos; Gicquel, Brigitte; Cole, Stewart T; Brodin, Priscille; Pym, Alexander S; Dalemans, Wilfried; Cohen, Joe; Lobet, Yves; Goonetilleke, Nilu; McShane, Helen; Hill, Adrian; Parish, Tanya; Smith, Debbie; Stoker, Neil G; Lowrie, Douglas B; Källenius, Gunilla; Svenson, Stefan; Pawlowski, Andrzej; Blake, Karen; Marsh, Philip D

    2005-01-01

    The TB Vaccine Cluster project funded by the EU Fifth Framework programme aims to provide novel vaccines against tuberculosis that are suitable for evaluation in humans. This paper describes the studies of the protective efficacy of vaccines in a guinea pig aerosol-infection model of primary tuberculosis. The objective was to conduct comparative evaluations of vaccines that had previously demonstrated efficacy in other animal models. Groups of 6 guinea pigs were immunized with vaccines provided by the relevant EU Vaccine Cluster partners. Survival over 17 or 26 weeks was used as the principal measure of vaccine efficacy following aerosol challenge with H37Rv. Counts of mycobacteria in lungs and spleens, and histopathological changes in the lungs, were also used to provide evidence of protection. A total of 24 vaccines were evaluated in 4 experiments each of a different design. A heterologous prime-boost strategy of DNA and MVA, each expressing Ag85A and a fusion protein of ESAT-6 and Ag85B in adjuvant, protected the guinea pigs to the same extent as BCG. Genetically modified BCG vaccines and boosted BCG strategies also protected guinea pigs to the same extent as BCG but not statistically significantly better. A relatively high aerosol-challenge dose and evaluation over a protracted time post-challenge allowed superior protection over BCG to be demonstrated by BCG boosted with MVA and fowl pox vectors expressing Ag85A.

  11. Cost-effectiveness of novel vaccines for tuberculosis control: a decision analysis study

    PubMed Central

    2011-01-01

    Background The development of a successful new tuberculosis (TB) vaccine would circumvent many limitations of current diagnostic and treatment practices. However, vaccine development is complex and costly. We aimed to assess the potential cost effectiveness of novel vaccines for TB control in a sub-Saharan African country - Zambia - relative to the existing strategy of directly observed treatment, short course (DOTS) and current level of bacille Calmette-Guérin (BCG) vaccination coverage. Methods We conducted a decision analysis model-based simulation from the societal perspective, with a 3% discount rate and all costs expressed in 2007 US dollars. Health outcomes and costs were projected over a 30-year period, for persons born in Zambia (population 11,478,000 in 2005) in year 1. Initial development costs for single vaccination and prime-boost strategies were prorated to the Zambian share (0.398%) of global BCG vaccine coverage for newborns. Main outcome measures were TB-related morbidity, mortality, and costs over a range of potential scenarios for vaccine efficacy. Results Relative to the status quo strategy, a BCG replacement vaccine administered at birth, with 70% efficacy in preventing rapid progression to TB disease after initial infection, is estimated to avert 932 TB cases and 422 TB-related deaths (prevention of 199 cases/100,000 vaccinated, and 90 deaths/100,000 vaccinated). This would result in estimated net savings of $3.6 million over 30 years for 468,073 Zambians born in year 1 of the simulation. The addition of a booster at age 10 results in estimated savings of $5.6 million compared to the status quo, averting 1,863 TB cases and 1,011 TB-related deaths (prevention of 398 cases/100,000 vaccinated, and of 216 deaths/100,000 vaccinated). With vaccination at birth alone, net savings would be realized within 1 year, whereas the prime-boost strategy would require an additional 5 years to realize savings, reflecting a greater initial development cost

  12. Adenovirus type 35-vectored tuberculosis vaccine has an acceptable safety and tolerability profile in healthy, BCG-vaccinated, QuantiFERON(®)-TB Gold (+) Kenyan adults without evidence of tuberculosis.

    PubMed

    Walsh, Douglas S; Owira, Victorine; Polhemus, Mark; Otieno, Lucas; Andagalu, Ben; Ogutu, Bernhards; Waitumbi, John; Hawkridge, Anthony; Shepherd, Barbara; Pau, Maria Grazia; Sadoff, Jerald; Douoguih, Macaya; McClain, J Bruce

    2016-05-05

    In a Phase 1 trial, we evaluated the safety of AERAS-402, an adenovirus 35-vectored TB vaccine candidate expressing 3 Mycobacterium tuberculosis (Mtb) immunodominant antigens, in subjects with and without latent Mtb infection. HIV-negative, BCG-vaccinated Kenyan adults without evidence of tuberculosis, 10 QuantiFERON(®)-TB Gold In-Tube test (QFT-G)(-) and 10 QFT-G(+), were randomized 4:1 to receive AERAS-402 or placebo as two doses, on Days 0 and 56, with follow up to Day 182. There were no deaths, serious adverse events or withdrawals. For 1 AERAS-402 QFT-G(-) and 1 AERAS-402 QFT-G(+) subject, there were 3 self-limiting severe AEs of injection site pain: 1 after the first vaccination and 1 after each vaccination, respectively. Two additional severe AEs considered vaccine-related were reported after the first vaccination in AERAS-402 QFT-G(+) subjects: elevated blood creatine phosphokinase and neutropenia, the latter slowly improving but remaining abnormal until study end. AERAS-402 was not detected in urine or throat cultures for any subject. In intracellular cytokine staining studies, curtailed by technical issues, we saw modest CD4+ and CD8+ T cell responses to Mtb Ag85A/b peptide pools among both QFT-G(-) and (+) subjects, with trends in the CD4+ T cells suggestive of boosting after the second vaccine dose, slightly more so in QFT-G(+) subjects. CD4+ and CD8+ responses to Mtb antigen TB10.4 were minimal. Increases in Adenovirus 35 neutralizing antibodies from screening to end of study, seen in 50% of AERAS-402 recipients, were mostly minimal. This small study confirms acceptable safety and tolerability profiles for AERAS-402, in line with other Phase 1 studies of AERAS-402, now to include QFT-G(+) subjects. Published by Elsevier Ltd.

  13. Development of plant-based mucosal vaccines against widespread infectious diseases.

    PubMed

    Salyaev, Rurick K; Rigano, Maria Manuela; Rekoslavskaya, Natalya I

    2010-08-01

    Mucosal vaccination is a perspective for the control of infectious diseases, since it is capable of inducing humoral and cell-mediated responses. In addition, the delivery of vaccines to mucosal surfaces makes immunization practice safe and acceptable, and eliminates needle-associated risks. Transgenic plants can be used as bioreactors for the production of mucosally delivered protective antigens. This technology shows great promise to simplify and decrease the cost of vaccine delivery. Herein, we review the development of mucosally administered vaccines expressed in transgenic plants. In particular, we evaluate the advantages and disadvantages of using plants for the production of mucosal vaccines against widespread infectious diseases such as HIV, hepatitis B and TB.

  14. Vaccination Against Porcine Circovirus-2 Reduces Severity of Tuberculosis in Wild Boar.

    PubMed

    Risco, David; Bravo, María; Martínez, Remigio; Torres, Almudena; Gonçalves, Pilar; Cuesta, Jesús; García-Jiménez, Waldo; Cerrato, Rosario; Iglesias, Rocío; Galapero, Javier; Serrano, Emmanuel; Gómez, Luis; Fernández-Llario, Pedro; Hermoso de Mendoza, Javier

    2018-03-09

    Tuberculosis (TB) in wild boar (Sus scrofa) may be affected by coinfections with other pathogens, such as porcine circovirus type 2 (PCV2). Therefore, sanitary measures focused on controlling PCV2 could be useful in reducing the impact of TB in this wild suid. The aim of this study was to explore whether vaccination against PCV2 targeting young animals affects TB prevalence and TB severity in wild boar. The study was conducted on a game estate in mid-western Spain. Seventy animals of ages ranging from 4 to 8 months were captured, individually identified, vaccinated against PCV2 and released, forming a vaccinated group. Not-captured animals cohabiting with the vaccinated wild boar constituted the control group. Animals from both groups were hunted between 2013 and 2016 and a TB diagnosis based on pathological assessment and microbiological culture was made in all of them. The effect of PCV2 vaccination on TB prevalence and severity was explored using generalized lineal models. Whereas TB prevalence was similar in vaccinated and control groups (54.55 vs. 57.78%), vaccinated animals showed less probabilities to develop generalized TB lesions. Furthermore, mean TB severity score was significantly lower in vaccinated animals (1.55 vs. 2.42) suggesting a positive effect of PCV2 vaccination.

  15. Tuberculosis vaccines: time to think about the next generation.

    PubMed

    Kaufmann, Stefan H E

    2013-04-01

    Efforts over the last 2 decades have led to a rich research and development pipeline of tuberculosis (TB) vaccines. Although none of the candidates has successfully completed the clinical trial pipeline, many are under advanced clinical assessment. These vaccines aim at prevention of active TB, with most of them being considered for preexposure with recent additions for postexposure or multistage administration. A few therapeutic vaccines are under clinical assessment, as well. Preexposure vaccination with the licensed TB vaccine BCG prevents severe forms of TB in children but not in adolescents and adults. The current vaccine pipeline does not include strategies which prevent or eliminate infection with the causative agent Mycobacterium tuberculosis (Mtb). Rather in a best-case scenario, they are quantitatively superior to BCG in preventing active TB over prolonged periods of time, ideally lifelong in the face of latent Mtb infection. Qualitatively superior vaccines should be capable of preventing or eliminating Mtb infection, in this way eliminating the risk of TB reactivation. The time is now ripe to exploit radically new strategies to achieve this goal. Copyright © 2013. Published by Elsevier Ltd.

  16. Development of a POC Test for TB Based on Multiple Immunodominant Epitopes of M. tuberculosis Specific Cell-Wall Proteins

    PubMed Central

    Gonzalez, Jesus M.; Francis, Bryan; Burda, Sherri; Hess, Kaitlyn; Behera, Digamber; Gupta, Dheeraj; Agarwal, Ashutosh Nath; Verma, Indu; Verma, Ajoy; Myneedu, Vithal Prasad; Niedbala, Sam; Laal, Suman

    2014-01-01

    The need for an accurate, rapid, simple and affordable point-of-care (POC) test for Tuberculosis (TB) that can be implemented in microscopy centers and other peripheral health-care settings in the TB-endemic countries remains unmet. This manuscript describes preliminary results of a new prototype rapid lateral flow TB test based on detection of antibodies to immunodominant epitopes (peptides) derived from carefully selected, highly immunogenic M. tuberculosis cell-wall proteins. Peptide selection was initially based on recognition by antibodies in sera from TB patients but not in PPD-/PPD+/BCG-vaccinated individuals from TB-endemic settings. The peptides were conjugated to BSA; the purified peptide-BSA conjugates striped onto nitrocellulose membrane and adsorbed onto colloidal gold particles to devise the prototype test, and evaluated for reactivity with sera from 3 PPD-, 29 PPD+, 15 PPD-unknown healthy subjects, 10 patients with non-TB lung disease and 124 smear-positive TB patients. The assay parameters were adjusted to determine positive/negative status within 15 minutes via visual or instrumented assessment. There was minimal or no reactivity of sera from non-TB subjects with the striped BSA-peptides demonstrating the lack of anti-peptide antibodies in subjects with latent TB and/or BCG vaccination. Sera from most TB patients demonstrated reactivity with one or more peptides. The sensitivity of antibody detection ranged from 28–85% with the 9 BSA-peptides. Three peptides were further evaluated with sera from 400 subjects, including additional PPD-/PPD+/PPD-unknown healthy contacts, close hospital contacts and household contacts of untreated TB patients, patients with non-TB lung disease, and HIV+TB- patients. Combination of the 3 peptides provided sensitivity and specificity>90%. While the final fully optimized lateral flow POC test for TB is under development, these preliminary results demonstrate that an antibody-detection based rapid POC lateral flow test

  17. High Antigen Dose Is Detrimental to Post-Exposure Vaccine Protection against Tuberculosis.

    PubMed

    Billeskov, Rolf; Lindenstrøm, Thomas; Woodworth, Joshua; Vilaplana, Cristina; Cardona, Pere-Joan; Cassidy, Joseph P; Mortensen, Rasmus; Agger, Else Marie; Andersen, Peter

    2017-01-01

    Mycobacterium tuberculosis (Mtb), the etiologic agent of tuberculosis (TB), causes 1.8M deaths annually. The current vaccine, BCG, has failed to eradicate TB leaving 25% of the world's population with latent Mtb infection (LTBI), and 5-10% of these people will reactivate and develop active TB. An efficient therapeutic vaccine targeting LTBI could have an enormous impact on global TB incidence, and could be an important aid in fighting multidrug resistance, which is increasing globally. Here we show in a mouse model using the H56 (Ag85B-ESAT-6-Rv2660) TB vaccine candidate that post-exposure, but not preventive, vaccine protection requires low vaccine antigen doses for optimal protection. Loss of protection from high dose post-exposure vaccination was not associated with a loss of overall vaccine response magnitude, but rather with greater differentiation and lower functional avidity of vaccine-specific CD4 T cells. High vaccine antigen dose also led to a decreased ability of vaccine-specific CD4 T cells to home into the Mtb-infected lung parenchyma, a recently discovered important feature of T cell protection in mice. These results underscore the importance of T cell quality rather than magnitude in TB-vaccine protection, and the significant role that antigen dosing plays in vaccine-mediated protection.

  18. Potential impact of spatially targeted adult tuberculosis vaccine in Gujarat, India

    PubMed Central

    Chatterjee, Susmita; Rao, Krishna D.; Dowdy, David W.

    2016-01-01

    Some of the most promising vaccines in the pipeline for tuberculosis (TB) target adolescents and adults. Unlike for childhood vaccines, high-coverage population-wide vaccination is significantly more challenging for adult vaccines. Here, we aimed to estimate the impact of vaccine delivery strategies that were targeted to high-incidence geographical ‘hotspots’ compared with randomly allocated vaccination. We developed a spatially explicit mathematical model of TB transmission that distinguished these hotspots from the general population. We evaluated the impact of targeted and untargeted vaccine delivery strategies in India—a country that bears more than 25% of global TB burden, and may be a potential early adopter of the vaccine. We collected TB notification data and conducted a demonstration study in the state of Gujarat to validate our estimates of heterogeneity in TB incidence. We then projected the impact of randomly vaccinating 8% of adults in a single mass campaign to a spatially targeted vaccination preferentially delivered to 80% of adults in the hotspots, with both strategies augmented by continuous adolescent vaccination. In consultation with vaccine developers, we considered a vaccine efficacy of 60%, and evaluated the population-level impact after 10 years of vaccination. Spatial heterogeneity in TB notification (per 100 000/year) was modest in Gujarat: 190 in the hotspots versus 125 in the remaining population. At this level of heterogeneity, the spatially targeted vaccination was projected to reduce TB incidence by 28% after 10 years, compared with a 24% reduction projected to achieve via untargeted vaccination—a 1.17-fold augmentation in the impact of vaccination by spatially targeting. The degree of the augmentation was robust to reasonable variation in natural history assumptions, but depended strongly on the extent of spatial heterogeneity and mixing between the hotspot and general population. Identifying high-incidence hotspots and

  19. Mycobacterium tuberculosis: approach to development of improved strategies for disease control through vaccination and immunodiagnosis.

    PubMed

    Mirlekar, B; Pathak, S; Pathade, G

    2013-01-01

    Tuberculosis is a major health problem throughout the world causing large number of deaths, more than that from any other single infectious disease. Estimates till date ascertain the fact that Tuberculosis (TB) is continuing to be the leading cause of death worldwide. The infection from single infectious agent Mycobacterium tuberculosis is killing about 3 million individuals every year and accounts for around 18.5% of all deaths in adults between the age group of 15 and 65. An average of 1.79 billion people, which constitutes roughly one-third of the world's population, is infected with the causative agent M. tuberculosis and is at risk of developing the disease. This situation highlights the relative shortcomings of the current treatment and diagnosis strategies for TB and the limited effectiveness of public health systems, particularly in resource-poor countries where the main TB burden lies. The timely identification of persons infected with Mycobacterium tuberculosis and rapid laboratory confirmation of tuberculosis are two key factors for the treatment and prevention of the disease. Novel molecular assays for diagnosis and drug susceptibility testing offer several potential advantages over the above methods including faster turnaround times, very sensitive and specific detection of nucleic acids, and minimal, or possibly no, prior culture. The need for new technologies for rapid diagnosis of tuberculosis is clear. Most studies of mycobacterial immunity attributes focus on proliferation of T cells, production of cytokines and cytolytic activity. A proper vaccine for tuberculosis can be developed by using a combination of antigens and adjuvants capable of inducing appropriate and long-lasting T cell immunity. Development of new vaccines against TB should include some important aspects learned from BCG use such as mucosal routes of immunization; revaccination of BCG immunized subjects, booster immunization and prime-boost strategy with wild-type BCG, and other

  20. Integrating knowledge of Mycobacterium tuberculosis pathogenesis for the design of better vaccines.

    PubMed

    Mascart, Françoise; Locht, Camille

    2015-01-01

    Today, tuberculosis (TB) still remains one of the main global causes of mortality and morbidity, and an effective vaccine against both TB disease and Mycobacterium tuberculosis infection is essential to reach the updated post-2015 Millennium development goal of eradicating TB by 2050. During the last two decades much knowledge has accumulated on the pathogenesis of TB and the immune responses to infection by M. tuberculosis. Furthermore, many vaccine candidates are under development, and close to 20 of them have entered clinical assessment at various levels. Nevertheless, the M. tuberculosis-host interaction is very complex, and the full complexity of this interaction is still not sufficiently well understood to develop novel, rationally designed vaccines. However, some of the recent knowledge is now integrated into the design of various types of vaccine candidates to be used either as pre-exposure, as post-exposure or as therapeutic vaccines, as will be discussed in this paper.

  1. A functional whole blood assay to measure viability of mycobacteria, using reporter-gene tagged BCG or M.Tb (BCGlux/M.Tb lux).

    PubMed

    Newton, Sandra; Martineau, Adrian; Kampmann, Beate

    2011-09-14

    Functional assays have long played a key role in measuring of immunogenicity of a given vaccine. This is conventionally expressed as serum bactericidal titers. Studies of serum bactericidal titers in response to childhood vaccines have enabled us to develop and validate cut-off levels for protective immune responses and such cut-offs are in routine use. No such assays have been taken forward into the routine assessment of vaccines that induce primarily cell-mediated immunity in the form of effector T cell responses, such as TB vaccines. In the animal model, the performance of a given vaccine candidate is routinely evaluated in standardized bactericidal assays, and all current novel TB-vaccine candidates have been subjected to this step in their evaluation prior to phase 1 human trials. The assessment of immunogenicity and therefore likelihood of protective efficacy of novel anti-TB vaccines should ideally undergo a similar step-wise evaluation in the human models now, including measurements in bactericidal assays. Bactericidal assays in the context of tuberculosis vaccine research are already well established in the animal models, where they are applied to screen potentially promising vaccine candidates. Reduction of bacterial load in various organs functions as the main read-out of immunogenicity. However, no such assays have been incorporated into clinical trials for novel anti-TB vaccines to date. Although there is still uncertainty about the exact mechanisms that lead to killing of mycobacteria inside human macrophages, the interaction of macrophages and T cells with mycobacteria is clearly required. The assay described in this paper represents a novel generation of bactericidal assays that enables studies of such key cellular components with all other cellular and humoral factors present in whole blood without making assumptions about their relative individual contribution. The assay described by our group uses small volumes of whole blood and has already been

  2. High Antigen Dose Is Detrimental to Post-Exposure Vaccine Protection against Tuberculosis

    PubMed Central

    Billeskov, Rolf; Lindenstrøm, Thomas; Woodworth, Joshua; Vilaplana, Cristina; Cardona, Pere-Joan; Cassidy, Joseph P.; Mortensen, Rasmus; Agger, Else Marie; Andersen, Peter

    2018-01-01

    Mycobacterium tuberculosis (Mtb), the etiologic agent of tuberculosis (TB), causes 1.8M deaths annually. The current vaccine, BCG, has failed to eradicate TB leaving 25% of the world’s population with latent Mtb infection (LTBI), and 5–10% of these people will reactivate and develop active TB. An efficient therapeutic vaccine targeting LTBI could have an enormous impact on global TB incidence, and could be an important aid in fighting multidrug resistance, which is increasing globally. Here we show in a mouse model using the H56 (Ag85B-ESAT-6-Rv2660) TB vaccine candidate that post-exposure, but not preventive, vaccine protection requires low vaccine antigen doses for optimal protection. Loss of protection from high dose post-exposure vaccination was not associated with a loss of overall vaccine response magnitude, but rather with greater differentiation and lower functional avidity of vaccine-specific CD4 T cells. High vaccine antigen dose also led to a decreased ability of vaccine-specific CD4 T cells to home into the Mtb-infected lung parenchyma, a recently discovered important feature of T cell protection in mice. These results underscore the importance of T cell quality rather than magnitude in TB-vaccine protection, and the significant role that antigen dosing plays in vaccine-mediated protection. PMID:29379507

  3. Oral vaccination of cattle with heat inactivated Mycobacterium bovis does not compromise bovine TB diagnostic tests.

    PubMed

    Jones, Gareth J; Steinbach, Sabine; Sevilla, Iker A; Garrido, Joseba M; Juste, Ramon; Vordermeier, H Martin

    2016-12-01

    In this study we investigated whether oral uptake of a heat inactivated M. bovis wildlife vaccine by domestic cattle induced systemic immune responses that compromised the use of tuberculin or defined antigens in diagnostic tests for bovine TB. Positive skin test and blood-based IFN-γ release assay (IGRA) results were observed in all calves vaccinated via the parenteral route (i.e. intramuscular). In contrast, no positive responses to tuberculin or defined antigens were observed in either the skin test or IGRA test when performed in calves vaccinated via the oral route. In conclusion, our results suggest that the heat inactivated M. bovis vaccine could be used to vaccinate wildlife in a baited form in conjunction with the following in cattle: (i) continuation of existing tuberculin skin testing or novel skin test formats based on defined antigens; and (ii) the use of IGRA tests utilizing tuberculin or defined antigens. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  4. Mucosal BCG Vaccination Induces Protective Lung-Resident Memory T Cell Populations against Tuberculosis.

    PubMed

    Perdomo, Carolina; Zedler, Ulrike; Kühl, Anja A; Lozza, Laura; Saikali, Philippe; Sander, Leif E; Vogelzang, Alexis; Kaufmann, Stefan H E; Kupz, Andreas

    2016-11-22

    mechanisms of protection have remained elusive. Here we performed an in-depth analysis to dissect the immunological mechanisms associated with superior mucosal protection in the mouse model of TB. We found that mucosal, and not subcutaneous, BCG vaccination generates lung-resident memory T cell populations that confer protection against pulmonary TB. We establish a comprehensive phenotypic characterization of these populations, providing a framework for future vaccine development. Copyright © 2016 Perdomo et al.

  5. Novel GMO-Based Vaccines against Tuberculosis: State of the Art and Biosafety Considerations.

    PubMed

    Leunda, Amaya; Baldo, Aline; Goossens, Martine; Huygen, Kris; Herman, Philippe; Romano, Marta

    2014-06-16

    Novel efficient vaccines are needed to control tuberculosis (TB), a major cause of morbidity and mortality worldwide. Several TB vaccine candidates are currently in clinical and preclinical development. They fall into two categories, the one of candidates designed as a replacement of the Bacille Calmette Guérin (BCG) to be administered to infants and the one of sub-unit vaccines designed as booster vaccines. The latter are designed as vaccines that will be administered to individuals already vaccinated with BCG (or in the future with a BCG replacement vaccine). In this review we provide up to date information on novel tuberculosis (TB) vaccines in development focusing on the risk assessment of candidates composed of genetically modified organisms (GMO) which are currently evaluated in clinical trials. Indeed, these vaccines administered to volunteers raise biosafety concerns with respect to human health and the environment that need to be assessed and managed.

  6. Experimental animal modelling for TB vaccine development.

    PubMed

    Cardona, Pere-Joan; Williams, Ann

    2017-03-01

    Research for a novel vaccine to prevent tuberculosis is an urgent medical need. The current vaccine, BCG, has demonstrated a non-homogenous efficacy in humans, but still is the gold standard to be improved upon. In general, the main indicator for testing the potency of new candidates in animal models is the reduction of the bacillary load in the lungs at the acute phase of the infection. Usually, this reduction is similar to that induced by BCG, although in some cases a weak but significant improvement can be detected, but none of candidates are able to prevent establishment of infection. The main characteristics of several laboratory animals are reviewed, reflecting that none are able to simulate the whole characteristics of human tuberculosis. As, so far, no surrogate of protection has been found, it is important to test new candidates in several models in order to generate convincing evidence of efficacy that might be better than that of BCG in humans. It is also important to investigate the use of "in silico" and "ex vivo" models to better understand experimental data and also to try to replace, or at least reduce and refine experimental models in animals. Copyright © 2017. Published by Elsevier Ltd.

  7. A high ratio of IC31® adjuvant to antigen is necessary for H4 TB vaccine immunomodulation

    PubMed Central

    Aboutorabian, Sepideh; Hakimi, Jalil; Boudet, Florence; Montano, Sandrine; Dookie, Annie; Roque, Cristopher; Ausar, Salvador F; Rahman, Nausheen; Brookes, Roger H

    2015-01-01

    A tuberculosis (TB) vaccine consisting of a recombinant fusion protein (H4) and a novel TLR9 adjuvant (IC31) is in clinical development. To better understand the H4-IC31 ratio, we measured the binding capacity of IC31 for H4 protein and immunized mice with formulations that contained limiting to excess ratios of IC31 to H4. An immunomodulated H4-specific IFNγ response was only observed when IC31 was present in excess of H4. Since TLR expression is species-specific and the vaccine is intended to boost BCG-primed immunity, we questioned whether data in mice would translate to humans. To address this question, we used the fresh human Whole Blood (hWB) recovered from BCG-vaccinated subjects to screen H4-IC31 formulations. We found IC31 modulation in hWB to be quite distinct from the TLR4-Adjuvant. Unlike TLR4-Adjuvant, IC31 formulations did not induce the pro-inflammatory cytokine TNFα, but modulated a robust H4-specific IFNγ response after 12 d of culture. We then re-stimulated the fresh hWB of 5 BCG-primed subjects with formulations that had excess or limiting IC31 binding for H4 protein and again found that an immunomodulated H4-specific IFNγ response needed an excess of IC31. Finally, we monitored the zeta (ζ) potential of H4-IC31 formulations and found that the overall charge of H4-IC31 particles changes from negative to positive once IC31 is in greater than 9-fold excess. Using two diverse yet mutually supportive approaches, we confirm the need for an excess of IC31 adjuvant in H4 TB vaccine formulations and suggest surface potential may be an important factor. PMID:25997147

  8. A high ratio of IC31(®) adjuvant to antigen is necessary for H4 TB vaccine immunomodulation.

    PubMed

    Aboutorabian, Sepideh; Hakimi, Jalil; Boudet, Florence; Montano, Sandrine; Dookie, Annie; Roque, Cristopher; Ausar, Salvador F; Rahman, Nausheen; Brookes, Roger H

    2015-01-01

    A tuberculosis (TB) vaccine consisting of a recombinant fusion protein (H4) and a novel TLR9 adjuvant (IC31) is in clinical development. To better understand the H4-IC31 ratio, we measured the binding capacity of IC31 for H4 protein and immunized mice with formulations that contained limiting to excess ratios of IC31 to H4. An immunomodulated H4-specific IFNγ response was only observed when IC31 was present in excess of H4. Since TLR expression is species-specific and the vaccine is intended to boost BCG-primed immunity, we questioned whether data in mice would translate to humans. To address this question, we used the fresh human Whole Blood (hWB) recovered from BCG-vaccinated subjects to screen H4-IC31 formulations. We found IC31 modulation in hWB to be quite distinct from the TLR4-Adjuvant. Unlike TLR4-Adjuvant, IC31 formulations did not induce the pro-inflammatory cytokine TNFα, but modulated a robust H4-specific IFNγ response after 12 d of culture. We then re-stimulated the fresh hWB of 5 BCG-primed subjects with formulations that had excess or limiting IC31 binding for H4 protein and again found that an immunomodulated H4-specific IFNγ response needed an excess of IC31. Finally, we monitored the zeta (ζ) potential of H4-IC31 formulations and found that the overall charge of H4-IC31 particles changes from negative to positive once IC31 is in greater than 9-fold excess. Using two diverse yet mutually supportive approaches, we confirm the need for an excess of IC31 adjuvant in H4 TB vaccine formulations and suggest surface potential may be an important factor.

  9. Knowledge of tuberculosis and vaccine trial preparedness in Lima, Peru.

    PubMed

    Shu, E; Sobieszczyk, M E; Sal Y Rosas, V G; Segura, P; Galea, J T; Lecca, L; Sanchez, J; Lama, J R

    2017-12-01

    A safe, effective vaccine would improve tuberculosis (TB) control worldwide. Extensive community engagement will be essential to ensure the interest and participation of populations at highest risk. To inform the potential implementation of efficacy studies, we assessed TB knowledge, attitudes towards licensed vaccines and willingness to participate in future TB vaccine efficacy trials among 262 household contacts of 79 recently diagnosed pulmonary TB cases in Lima, Peru. Overall knowledge of TB was low. Only 41.6% of household contacts perceived themselves as being at high risk of acquiring TB. Slightly above half (54.2%) indicated willingness to participate in a TB vaccine trial. After clustered analysis adjusting for homogeneity among families, willingness to enroll was associated with belief that receiving all recommended vaccinations is important (adjusted OR [aOR] 3.28, P = 0.016), desire to know more about TB risk factors and clinical trials (aOR 2.60, P = 0.004), older age (aOR 1.02, P = 0.027) and TB knowledge (aOR 0.05, P = 0.039). Barriers to participation in TB vaccine trials exist among individuals at high risk for TB. Targeted education about TB risk factors, TB transmission and education about the clinical trial process will be critical for laying the groundwork for future vaccine trials.

  10. Future vaccination strategies against tuberculosis: thinking outside the box.

    PubMed

    Kaufmann, Stefan H E

    2010-10-29

    With almost a dozen vaccine candidates in clinical trials, tuberculosis (TB) research and development is finally reaping the first fruits of its labors. Vaccine candidates in clinical trials may prevent TB disease reactivation by efficiently containing the pathogen Mycobacterium tuberculosis (Mtb). Future research should target vaccines that achieve sterile eradication of Mtb or even prevent stable infection. These are ambitious goals that can be reached only by highly cooperative engagement of basic immunologists, vaccinologists, and clinical researchers--or in other words, by translation from basic immunology to vaccine research and development, as well as reverse translation of insights from clinical trials back to hypothesis-driven research in the basic laboratory. Here, we review current and future strategies toward the rational design of novel vaccines against TB, as well as the progress made thus far, and the hurdles that need to be overcome in the near and distant future. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Immunogenicity and protective efficacy of DMT liposome-adjuvanted tuberculosis subunit CTT3H vaccine

    PubMed Central

    Teng, Xindong; Tian, Maopeng; Li, Jianrong; Tan, Songwei; Yuan, Xuefeng; Yu, Qi; Jing, Yukai; Zhang, Zhiping; Yue, Tingting; Zhou, Lei; Fan, Xionglin

    2015-01-01

    Different strategies have been proposed for the development of protein subunit vaccine candidates for tuberculosis (TB), which shows better safety than other types of candidates and the currently used Bacillus Calmette-Guérin (BCG) vaccine. In order to develop more effective protein subunits depending on the mechanism of cell-mediated immunity against TB, a polyprotein CTT3H, based on 5 immunodominant antigens (CFP10, TB10.4, TB8.4, Rv3615c, and HBHA) with CD8+ epitopes of Mycobacterium tuberculosis, was constructed in this study. We vaccinated C57BL/6 mice with a TB subunit CTT3H protein in an adjuvant of dimethyldioctadecylammonium/monophosphoryl lipid A/trehalose 6,6′-dibehenate (DDA/MPL/TDB, DMT) liposome to investigate the immunogenicity and protective efficacy of this novel vaccine. Our results demonstrated that DMT liposome-adjuvanted CTT3H vaccine not only induced an antigen-specific CD4+ Th1 response, but also raised the number of PPD- and CTT3H-specific IFN-γ+ CD8+ T cells and elicited strong CTL responses against TB10.4, which provided more effective protection against a 60 CFU M. tuberculosis aerosol challenge than PBS control and DMT adjuvant alone. Our findings indicate that DMT-liposome is an effective adjuvant to stimulate CD8+ T cell responses and the DMT-adjuvanted subunit CTT3H vaccine is a promising candidate for the next generation of TB vaccine. PMID:25905680

  12. Immunogenicity and protective efficacy of DMT liposome-adjuvanted tuberculosis subunit CTT3H vaccine.

    PubMed

    Teng, Xindong; Tian, Maopeng; Li, Jianrong; Tan, Songwei; Yuan, Xuefeng; Yu, Qi; Jing, Yukai; Zhang, Zhiping; Yue, Tingting; Zhou, Lei; Fan, Xionglin

    2015-01-01

    Different strategies have been proposed for the development of protein subunit vaccine candidates for tuberculosis (TB), which shows better safety than other types of candidates and the currently used Bacillus Calmette-Guérin (BCG) vaccine. In order to develop more effective protein subunits depending on the mechanism of cell-mediated immunity against TB, a polyprotein CTT3H, based on 5 immunodominant antigens (CFP10, TB10.4, TB8.4, Rv3615c, and HBHA) with CD8(+) epitopes of Mycobacterium tuberculosis, was constructed in this study. We vaccinated C57BL/6 mice with a TB subunit CTT3H protein in an adjuvant of dimethyldioctadecylammonium/monophosphoryl lipid A/trehalose 6,6'-dibehenate (DDA/MPL/TDB, DMT) liposome to investigate the immunogenicity and protective efficacy of this novel vaccine. Our results demonstrated that DMT liposome-adjuvanted CTT3H vaccine not only induced an antigen-specific CD4(+) Th1 response, but also raised the number of PPD- and CTT3H-specific IFN-γ(+) CD8(+) T cells and elicited strong CTL responses against TB10.4, which provided more effective protection against a 60 CFU M. tuberculosis aerosol challenge than PBS control and DMT adjuvant alone. Our findings indicate that DMT-liposome is an effective adjuvant to stimulate CD8(+) T cell responses and the DMT-adjuvanted subunit CTT3H vaccine is a promising candidate for the next generation of TB vaccine.

  13. Prospects in Mycobacterium bovis Bacille Calmette et Guérin (BCG) Vaccine Diversity and Delivery: Why does BCG fail to protect against Tuberculosis?

    PubMed Central

    Moliva, Juan I.; Turner, Joanne; Torrelles, Jordi B.

    2015-01-01

    Mycobacterium tuberculosis (M.tb) infection leads to active tuberculosis (TB), a disease that kills one human every 18 seconds. Current therapies available to combat TB include chemotherapy and the preventative vaccine Mycobacterium bovis Bacille Calmette et Guérin (BCG). Increased reporting of drug resistant M.tb strains worldwide indicates that drug development cannot be the primary mechanism for eradication. BCG vaccination has been used globally for protection against childhood and disseminated TB, however, its efficacy at protecting against pulmonary TB in adult and aging populations is highly variable. In this regard, the immune response generated by BCG vaccination is incapable of sterilizing the lung post M.tb infection as indicated by the large proportion of individuals with latent TB infection that have received BCG. Although many new TB vaccine candidates have entered the development pipeline, only a few have moved to human clinical trials; where they showed no efficacy and/or were withdrawn due to safety regulations. These trials highlight our limited understanding of protective immunity against the development of active TB. Here, we discuss current vaccination strategies and their impact on the generation and sustainability of protective immunity against TB. PMID:26319069

  14. Novel GMO-Based Vaccines against Tuberculosis: State of the Art and Biosafety Considerations

    PubMed Central

    Leunda, Amaya; Baldo, Aline; Goossens, Martine; Huygen, Kris; Herman, Philippe; Romano, Marta

    2014-01-01

    Novel efficient vaccines are needed to control tuberculosis (TB), a major cause of morbidity and mortality worldwide. Several TB vaccine candidates are currently in clinical and preclinical development. They fall into two categories, the one of candidates designed as a replacement of the Bacille Calmette Guérin (BCG) to be administered to infants and the one of sub-unit vaccines designed as booster vaccines. The latter are designed as vaccines that will be administered to individuals already vaccinated with BCG (or in the future with a BCG replacement vaccine). In this review we provide up to date information on novel tuberculosis (TB) vaccines in development focusing on the risk assessment of candidates composed of genetically modified organisms (GMO) which are currently evaluated in clinical trials. Indeed, these vaccines administered to volunteers raise biosafety concerns with respect to human health and the environment that need to be assessed and managed. PMID:26344627

  15. Modulation of autophagy as a strategy for development of new vaccine candidates against tuberculosis.

    PubMed

    Flores-Valdez, Mario Alberto; Segura-Cerda, Cristian Alfredo; Gaona-Bernal, Jorge

    2018-05-01

    Effective prevention of tuberculosis (Tb) would undoubtedly be of paramount relevance in the control of its global burden, which resulted in more than 6 million new cases in 2016. Research aimed to improve the current vaccine, Bacillus Calmette- Guérin (BCG), or directed to develop new candidates, has taken into account the interaction between the host and Mycobacterium tuberculosis (Mtb). Recently, autophagy, an intracellular process of the host, has been shown to act as a mechanism that contributes to bacilli clearance in vitro and in vivo. Stimulation of autophagy, if correctly balanced, is an approach that has the potential to enhance the immune response of the host, and offers new avenues for developing immunogens that may give an improved protection upon immunization, given that in fact, some recent rBCG vaccine candidates have been shown to modulate autophagy. In this Discussion, we analyze the role of autophagy in the context of mycobacterial infection, its modulation via mycobacterial elements, and the management of host response as an alternative to develop new, hopefully improved, Tb-vaccine candidates. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Curing TB with open science.

    PubMed

    Ekins, Sean; Williams, Antony J

    2014-03-01

    There are many funded efforts going on focused on tuberculosis research and drug or vaccine development. There is little if any global coordination or collaboration and subsequently there are likely to be huge data silos and duplication of efforts. We now propose steps to remedy this by fostering more open science in TB research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Breaking Transmission with Vaccines: The Case of Tuberculosis.

    PubMed

    Gonzalo-Asensio, Jesus; Aguilo, Nacho; Marinova, Dessislava; Martin, Carlos

    2017-07-01

    Members of the Mycobacterium tuberculosis complex (MTBC) have evolved causing tuberculosis (TB) in different mammalian hosts. MTBC ecotypes have adapted to diverse animal species, with M. bovis being the most common cause of TB in livestock. Cattle-to-human transmission of M. bovis through ingestion of raw milk was common before introduction of the pasteurization process. TB in humans is mainly caused by M. tuberculosis . This bacterium is considered a genetically clonal pathogen that has coevolved with humans due to its ability to manipulate and subvert the immune response. TB is a major public health problem due to airborne person-to-person transmission of M. tuberculosis . The essential yet unanswered question on the natural history of TB is when M. tuberculosis decides to establish latent infection in the host (resambling the lysogenic cycle of lambda phage) or to cause pulmonary disease (comparable to the lytic cycle of lambda phage). In this latter case, M. tuberculosis kills the host with the aim of achieving transmission to new hosts. Combating the TB epidemic requires stopping transmission. M. bovis BCG, the present vaccine against TB, is derived from M. bovis and only protects against disseminated forms of TB. Thus, a priority in TB research is development of new effective vaccines to prevent pulmonary disease. Attenuated vaccines based on M. tuberculosis as MTBVAC are potential candidates that could contribute to break the TB transmission cycle.

  18. Assessment of BCG and inactivated Mycobacterium bovis vaccines in an experimental tuberculosis infection model in sheep.

    PubMed

    Balseiro, Ana; Altuzarra, Raúl; Vidal, Enric; Moll, Xavier; Espada, Yvonne; Sevilla, Iker A; Domingo, Mariano; Garrido, Joseba M; Juste, Ramón A; Prieto, Miguel; Pérez de Val, Bernat

    2017-01-01

    Animal tuberculosis (TB) is a complex animal health problem that causes disruption to trade and significant economic losses. TB involves a multi-host system where sheep, traditionally considered a rare host of this infection, have been recently included. The aims of this study were to develop an experimental TB infection model in sheep with a Mycobacterium caprae field strain isolated from a tuberculous diseased ewe, and to use this to evaluate the safety and efficacy of two vaccines against TB in sheep, the live-attenuated M. bovis BCG vaccine (Danish strain) and a heat-inactivated M. bovis (HIMB) vaccine. Eighteen 2 month-old lambs were experimentally challenged with M. caprae by the endotracheal route (1.5 × 103 CFU). They were separated per treatment group into parenterally vaccinated with a live BCG Danish strain vaccine (n = 6), orally vaccinated with a suspension of HIMB (n = 6) and unvaccinated controls (n = 6). Clinical, immunological, pathological and bacteriological parameters of infection were measured. All lambs were successfully infected and developed gross TB lesions in the respiratory system. The BCG vaccine conferred considerable protection against experimental TB in lambs, as measured by a reduction of the gross lesion volumes and bacterial load. However, HIMB vaccinated animals did not show protection. This study proposes a reliable new experimental model for a better understanding of tuberculosis in sheep. BCG vaccination offers an effective prospect for controlling the disease. Moreover alternative doses and/or routes of administration should be considered to evaluate the efficacy of the HIMB vaccine candidate.

  19. Immune Responses to Bacillus Calmette–Guérin Vaccination: Why Do They Fail to Protect against Mycobacterium tuberculosis?

    PubMed Central

    Moliva, Juan I.; Turner, Joanne; Torrelles, Jordi B.

    2017-01-01

    Mycobacterium tuberculosis (M.tb), the causative agent of tuberculosis (TB), is the current leading cause of death due to a single infectious organism. Although curable, the broad emergence of multi-, extensive-, extreme-, and total-drug resistant strains of M.tb has hindered eradication efforts of this pathogen. Furthermore, computational models predict a quarter of the world’s population is infected with M.tb in a latent state, effectively serving as the largest reservoir for any human pathogen with the ability to cause significant morbidity and mortality. The World Health Organization has prioritized new strategies for improved vaccination programs; however, the lack of understanding of mycobacterial immunity has made it difficult to develop new successful vaccines. Currently, Mycobacterium bovis bacillus Calmette–Guérin (BCG) is the only vaccine approved for use to prevent TB. BCG is highly efficacious at preventing meningeal and miliary TB, but is at best 60% effective against the development of pulmonary TB in adults and wanes as we age. In this review, we provide a detailed summary on the innate immune response of macrophages, dendritic cells, and neutrophils in response to BCG vaccination. Additionally, we discuss adaptive immune responses generated by BCG vaccination, emphasizing their specific contributions to mycobacterial immunity. The success of future vaccines against TB will directly depend on our understanding of mycobacterial immunity. PMID:28424703

  20. Toward Novel Vaccines Against Tuberculosis: Current Hopes and Obstacles

    PubMed Central

    Thaiss, Christoph A.; Kaufmann, Stefan H.E.

    2010-01-01

    Approximately 2 million people die of tuberculosis (TB) each year. The current vaccine, Bacille Calmette-Guérin (BCG), albeit widely employed, does not protect against adult pulmonary disease, and new vaccines are urgently needed to reduce the incidence of TB worldwide. New insights into the cellular and molecular mechanisms that underlie the interactions between Mycobacterium tuberculosis and its host have been exploited to develop novel vaccine candidates that recently have entered clinical trials. This review provides a brief overview of different approaches toward a new vaccination strategy and summarizes major challenges for the next decade. PMID:21165340

  1. Convergent ethical issues in HIV/AIDS, tuberculosis and malaria vaccine trials in Africa: Report from the WHO/UNAIDS African AIDS Vaccine Programme's Ethics, Law and Human Rights Collaborating Centre consultation, 10-11 February 2009, Durban, South Africa

    PubMed Central

    2010-01-01

    Background Africa continues to bear a disproportionate share of the global HIV/AIDS, tuberculosis (TB) and malaria burden. The development and distribution of safe, effective and affordable vaccines is critical to reduce these epidemics. However, conducting HIV/AIDS, TB, and/or malaria vaccine trials simultaneously in developing countries, or in populations affected by all three diseases, is likely to result in numerous ethical challenges. Methods In order to explore convergent ethical issues in HIV/AIDS, TB and malaria vaccine trials in Africa, the Ethics, Law and Human Rights Collaborating Centre of the WHO/UNAIDS African AIDS Vaccine Programme hosted a consultation on the Convergent Ethical Issues in HIV/AIDS, TB and Malaria Vaccine Trials in Africa in Durban, South Africa on the 10-11 February 2009. Results Key cross cutting ethical issues were prioritized during the consultation as community engagement; ancillary care obligations; care and treatment; informed consent; and resource sharing. Conclusion The consultation revealed that while there have been few attempts to find convergence on ethical issues between HIV/AIDS, TB and malaria vaccine trial fields to date, there is much common ground and scope for convergence work between stakeholders in the three fields. PMID:20211030

  2. Convergent ethical issues in HIV/AIDS, tuberculosis and malaria vaccine trials in Africa: Report from the WHO/UNAIDS African AIDS Vaccine Programme's Ethics, Law and Human Rights Collaborating Centre consultation, 10-11 February 2009, Durban, South Africa.

    PubMed

    Mamotte, Nicole; Wassenaar, Douglas; Koen, Jennifer; Essack, Zaynab

    2010-03-09

    Africa continues to bear a disproportionate share of the global HIV/AIDS, tuberculosis (TB) and malaria burden. The development and distribution of safe, effective and affordable vaccines is critical to reduce these epidemics. However, conducting HIV/AIDS, TB, and/or malaria vaccine trials simultaneously in developing countries, or in populations affected by all three diseases, is likely to result in numerous ethical challenges. In order to explore convergent ethical issues in HIV/AIDS, TB and malaria vaccine trials in Africa, the Ethics, Law and Human Rights Collaborating Centre of the WHO/UNAIDS African AIDS Vaccine Programme hosted a consultation on the Convergent Ethical Issues in HIV/AIDS, TB and Malaria Vaccine Trials in Africa in Durban, South Africa on the 10-11 February 2009. Key cross cutting ethical issues were prioritized during the consultation as community engagement; ancillary care obligations; care and treatment; informed consent; and resource sharing. The consultation revealed that while there have been few attempts to find convergence on ethical issues between HIV/AIDS, TB and malaria vaccine trial fields to date, there is much common ground and scope for convergence work between stakeholders in the three fields.

  3. Recent advances towards tuberculosis control: vaccines and biomarkers

    PubMed Central

    Weiner, J; Kaufmann, S H E

    2014-01-01

    Weiner 3rd J, Kaufmann SHE (Max Planck Institute for Infection Biology, Berlin, Germany). Recent advances towards tuberculosis control: vaccines and biomarkers. (Review). J Intern Med 2014; 275: 467–480. Of all infectious diseases, tuberculosis (TB) remains one of the most important causes of morbidity and mortality. Recent advances in understanding the biology of Mycobacterium tuberculosis (Mtb) infection and the immune response of the infected host have led to the development of several new vaccines, a number of which are already undergoing clinical trials. These include pre-exposure prime vaccines, which could replace bacille Calmette–Guérin (BCG), and pre-exposure booster vaccines given in addition to BCG. Infants are the target population of these two types of vaccines. In addition, several postexposure vaccines given during adolescence or adult life, in addition to BCG as a priming vaccine during infancy, are undergoing clinical testing. Therapeutic vaccines are currently being assessed for their potential to cure active TB as an adjunct to chemotherapy. BCG replacement vaccines are viable recombinant BCG or double-deletion mutants of Mtb. All booster vaccines are composed of one or several antigens, either expressed by viral vectors or formulated with adjuvants. Therapeutic vaccines are killed mycobacterial preparations. Finally, multivariate biomarkers and biosignatures are being generated from high-throughput data with the aim of providing better diagnostic tools to specifically determine TB progression. Here, we provide a technical overview of these recent developments as well of the relevant computational approaches and highlight the obstacles that still need to be overcome. PMID:24635488

  4. Impact of Targeted Tuberculosis Vaccination Among a Mining Population in South Africa: A Model-Based Study.

    PubMed

    Shrestha, Sourya; Chihota, Violet; White, Richard G; Grant, Alison D; Churchyard, Gavin J; Dowdy, David W

    2017-12-15

    Optimizing the use of new tools, such as vaccines, may play a crucial role in reaching global targets for tuberculosis (TB) control. Some of the most promising candidate vaccines target adults, although high-coverage mass vaccinations may be logistically more challenging among this population than among children. Vaccine-delivery strategies that target high-risk groups or settings might yield proportionally greater impact than do those that target the general population. We developed an individual-based TB transmission model representing a hypothetical population consisting of people who worked in South African gold mines or lived in associated labor-sending communities. We simulated the implementation of a postinfection adult vaccine with 60% efficacy and a mean effect duration of 10 years. We then compared the impact of a mine-targeted vaccination strategy, in which miners were vaccinated while in the mines, with that of a community-targeted strategy, in which random individuals within the labor-sending communities were vaccinated. Mine-targeted vaccination averted an estimated 0.37 TB cases per vaccine dose compared with 0.25 for community-targeted vaccination, for a relative efficacy of 1.46 (95% range, 1.13-1.91). The added benefit of mine-targeted vaccination primarily reflected the disproportionate demographic burden of TB among the population of adult males as a whole. As novel vaccines for TB are developed, venue-based vaccine delivery that targets high-risk demographic groups may improve both vaccine feasibility and the impact on transmission. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. BCG vaccination drives accumulation and effector function of innate lymphoid cells in murine lungs.

    PubMed

    Steigler, Pia; Daniels, Naomi J; McCulloch, Tim R; Ryder, Brin M; Sandford, Sarah K; Kirman, Joanna R

    2018-04-01

    The tuberculosis (TB) vaccine bacille Calmette-Guérin (BCG) prevents disseminated childhood TB; however, it fails to protect against the more prevalent pulmonary TB. Limited understanding of the immune response to Mycobacterium tuberculosis, the causative agent of TB, has hindered development of improved vaccines. Although memory CD4 T cells are considered the main mediators of protection against TB, recent studies suggest there are other key subsets that contribute to antimycobacterial immunity. To that end, innate cells may be involved in the protective response. In this study, we investigated the primary response of innate lymphoid cells (ILCs) to BCG exposure. Using a murine model, we showed that ILCs increased in number in the lungs and lymph nodes in response to BCG vaccination. Additionally, there was significant production of the antimycobacterial cytokine IFN-γ by ILCs. As ILCs are located at mucosal sites, it was investigated whether mucosal vaccination (intranasal) stimulated an enhanced response compared to the traditional vaccination approach (intradermal or subcutaneous). Indeed, in response to intranasal vaccination, the number of ILCs, and IFN-γ production in NK cells and ILC1s in the lungs and lymph nodes, were higher than that provoked through intradermal or subcutaneous vaccination. This work provides the first evidence that BCG vaccination activates ILCs, paving the way for future research to elucidate the protective potential of ILCs against mycobacterial infection. Additionally, the finding that lung ILCs respond rigorously to mucosal vaccination may have implications for the delivery of novel TB vaccines. © 2018 Australasian Society for Immunology Inc.

  6. Modelling the cost-effectiveness of a new infant vaccine to prevent tuberculosis disease in children in South Africa

    PubMed Central

    2014-01-01

    Background Tuberculosis remains the leading cause of death in South Africa. A number of potential new TB vaccine candidates have been identified and are currently in clinical trials. One such candidate is MVA85A. This study aimed to estimate the cost-effectiveness of adding the MVA85A vaccine as a booster to the BCG vaccine in children from the perspective of the South African government. Methods The cost-effectiveness was assessed by employing Decision Analytic Modelling, through the use of a Markov model. The model compared the existing strategy of BCG vaccination to a new strategy in which infants receive BCG and a booster vaccine, MVA85A, at 4 months of age. The costs and outcomes of the two strategies are estimated through modelling the vaccination of a hypothetical cohort of newborns and following them from birth through to 10 years of age, employing 6-monthly cycles. Results The results of the cost-effectiveness analysis indicate that the MVA85A strategy is both more costly and more effective – there are fewer TB cases and deaths from TB than BCG alone. The South African government would need to spend an additional USD 1,105 for every additional TB case averted and USD 284,017 for every additional TB death averted. The threshold analysis shows that, if the efficacy of the MVA85A vaccine was 41.3% (instead of the current efficacy of 17.3%), the two strategies would have the same cost but more cases of TB and more deaths from TB would be prevented by adding the MVA85A vaccine to the BCG vaccine. In this case, the government chould consider the MVA85A strategy. Conclusions At the current level of efficacy, the MVA85A vaccine is neither effective nor cost-effective and, therefore, not a good use of limited resources. Nevertheless, this study contributes to developing a standardized Markov model, which could be used, in the future, to estimate the potential cost-effectiveness of new TB vaccines compared to the BCG vaccine, in children between the ages of 0

  7. Dihydrolipoamide dehydrogenase-Lpd (Rv0462)-specific T cell recall responses are higher in healthy household contacts of TB: a novel immunodominant antigen from M. tuberculosis.

    PubMed

    Devasundaram, Santhi; Raja, Alamelu

    2017-07-01

    The partial effectiveness against pulmonary tuberculosis (PTB), displayed by the existing tuberculosis (TB) vaccine, bacillus Calmette-Guérin (BCG), highlights the need for novel vaccines to replace or improve BCG. In TB immunology, antigen-specific cellular immune response is frequently considered indispensable. Latency-associated antigens are intriguing as targets for TB vaccine development. The mycobacterial protein, dihydrolipoamide dehydrogenase (Lpd; Rv0462), the third enzyme of the pyruvate dehydrogenase (PDH) complex, facilitates Mycobacterium tuberculosis to resist host reactive nitrogen intermediates. Multicolor flow cytometry analysis of whole-blood cultures showed higher Lpd-specific Th1 recall response (IFN-γ, TNF-α, and IL-2; P = 0.0006) and memory CD4 + and CD8 + T cells (CCR7 + CD45RA - and CCR7 - CD45RA - ) in healthy household contacts (HHC) of TB ( P < 0.0001), which is comparable with or higher than the standard antigens, ESAT-6 and CFP-10. The frequency of Lpd-specific multifunctional T cells was higher in HHC compared with PTB patients. However, there is no significant statistical correlation. Regulatory T cell (T reg ) analysis of HHCs and active TB patients demonstrated very low Lpd-specific CD4 + T regs relative to ESAT-6 and CFP-10. Our study demonstrates that the Lpd antigen induces a strong cellular immune response in healthy mycobacteria-infected individuals. In consideration of this population having demonstrated immunologic protection against active TB disease development, our data are encouraging about the possible use of Lpd as a target for further TB subunit vaccine development. © Society for Leukocyte Biology.

  8. Joint effect of MCP-1 genotype GG and MMP-1 genotype 2G/2G increases the likelihood of developing pulmonary tuberculosis in BCG-vaccinated individuals.

    PubMed

    Ganachari, Malathesha; Ruiz-Morales, Jorge A; Gomez de la Torre Pretell, Juan C; Dinh, Jeffrey; Granados, Julio; Flores-Villanueva, Pedro O

    2010-01-25

    We previously reported that the -2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the -1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the -2518 MCP-1 genotype GG and the -1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1.

  9. Joint Effect of MCP-1 Genotype GG and MMP-1 Genotype 2G/2G Increases the Likelihood of Developing Pulmonary Tuberculosis in BCG-Vaccinated Individuals

    PubMed Central

    Ganachari, Malathesha; Ruiz-Morales, Jorge A.; Gomez de la Torre Pretell, Juan C.; Dinh, Jeffrey; Granados, Julio; Flores-Villanueva, Pedro O.

    2010-01-01

    We previously reported that the – 2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the – 1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the – 2518 MCP-1 genotype GG and the – 1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1. PMID:20111728

  10. Polyfunctional CD4+ T Cells As Targets for Tuberculosis Vaccination

    PubMed Central

    Lewinsohn, Deborah A.; Lewinsohn, David M.; Scriba, Thomas J.

    2017-01-01

    Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of morbidity and mortality worldwide, despite the widespread use of the only licensed vaccine, Bacille Calmette Guerin (BCG). Eradication of TB will require a more effective vaccine, yet evaluation of new vaccine candidates is hampered by lack of defined correlates of protection. Animal and human studies of intracellular pathogens have extensively evaluated polyfunctional CD4+ T cells producing multiple pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-2) as a possible correlate of protection from infection and disease. In this study, we review the published literature that evaluates whether or not BCG and/or novel TB vaccine candidates induce polyfunctional CD4+ T cells and if these T cell responses correlate with vaccine-mediated protection. Ample evidence suggests that BCG and several novel vaccine candidates evaluated in animal models and humans induce polyfunctional CD4+ T cells. However, while a number of studies utilizing the mouse TB model support that polyfunctional CD4+ T cells are associated with vaccine-induced protection, other studies in mouse and human infants demonstrate no correlation between these T cell responses and protection. We conclude that induction of polyfunctional CD4+ T cells is certainly not sufficient and may not even be necessary to mediate protection and suggest that other functional attributes, such as additional effector functions, T cell differentiation state, tissue homing potential, or long-term survival capacity of the T cell may be equally or more important to promote protection. Thus, a correlate of protection for TB vaccine development remains elusive. Future studies should address polyfunctional CD4+ T cells within the context of more comprehensive immunological signatures of protection that include other functions and phenotypes of T cells as well as the full spectrum of immune cells and mediators that participate in the immune

  11. Next-Generation Vaccines Based on Bacille Calmette–Guérin

    PubMed Central

    Nieuwenhuizen, Natalie E.; Kaufmann, Stefan H. E.

    2018-01-01

    Tuberculosis (TB), caused by the intracellular bacterium Mycobacterium tuberculosis (Mtb), remains a major health threat. A live, attenuated mycobacterium known as Bacille Calmette–Guérin (BCG), derived from the causative agent of cattle TB, Mycobacterium bovis, has been in clinical use as a vaccine for 90 years. The current incidence of TB demonstrates that BCG fails to protect sufficiently against pulmonary TB, the major disease manifestation and source of dissemination. The protective efficacy of BCG is on average 50% but varies substantially with geographical location and is poorer in those with previous exposure to mycobacteria. BCG can also cause adverse reactions in immunocompromised individuals. However, BCG has contributed to reduced infant TB mortality by protecting against extrapulmonary TB. In addition, BCG has been associated with reduced general childhood mortality by stimulating immune responses. In order to improve the efficacy of BCG, two major strategies have been employed. The first involves the development of recombinant live mycobacterial vaccines with improved efficacy and safety. The second strategy is to boost BCG with subunit vaccines containing Mtb antigens. This article reviews recombinant BCG strains that have been tested against TB in animal models. This includes BCG strains that have been engineered to induce increased immune responses by the insertion of genes for Mtb antigens, mammalian cytokines, or host resistance factors, the insertion of bacterial toxin-derived adjuvants, and the manipulation of bacterial genes in order to increase antigen presentation and immune activation. Subunit vaccines for boosting BCG are also briefly discussed. PMID:29459859

  12. Modelling the impact of vaccination on tuberculosis in badgers.

    PubMed

    Hardstaff, J L; Bulling, M T; Marion, G; Hutchings, M R; White, P C L

    2013-07-01

    Tuberculosis (TB) in livestock, caused by Mycobacterium bovis, persists in many countries. In Britain, efforts to control TB through the culling of badgers (Meles meles), the principal wildlife host, have so far been unsuccessful, and there is significant interest in vaccination of badgers as an alternative or complementary strategy [corrected]. Using a simulation model, we show that where TB is self-contained within the badger population and there are no external sources of infection, limited-duration vaccination at a high level of efficacy can reduce or even eradicate TB from the badger population. However, where sources of external infection persist, benefits in TB reduction in badgers can only be achieved by ongoing, annual vaccination. Vaccination is likely to be most effective as part of an integrated disease management strategy incorporating a number of different approaches across the entire host community.

  13. Potential of polymeric particles as future vaccine delivery systems/adjuvants for parenteral and non-parenteral immunization against tuberculosis: A systematic review.

    PubMed

    Khademi, Farzad; Derakhshan, Mohammad; Yousefi-Avarvand, Arshid; Tafaghodi, Mohsen

    2018-02-01

    Production of effective tuberculosis (TB) vaccine is necessity. However, the development of new subunit vaccines is faced with concerns about their weak immunogenicity. To overcome such problems, polymers-based vaccine delivery systems have been proposed to be used via various routes. The purpose of this study was to determine the potential of polymeric particles as future vaccine delivery systems/adjuvants for parenteral and non-parenteral immunization against TB. PubMed, Scopus, Science-Direct, and the ISI web of knowledge databases were searched for related keywords. A total of 420 articles, written up to June 25, 2016, were collected on the potential of polymeric particles as TB vaccine delivery systems after parenteral and non-parenteral immunization. Thirty-one relevant articles were selected by applying inclusion and exclusion criteria. It was shown that the immunogenicity of TB vaccines had been improved by using biodegradable and non-biodegradable synthetic polymers as well as natural polymers and they are better able to enhance the humoral and cellular immune responses, compared to TB vaccines alone. The present study revealed that various polymeric particles, after M. tuberculosis challenge in animal models, provide long-lasting protection against TB. PLGA (poly (lactide-co-glycolide)) and chitosan polymers were widely used as TB vaccine delivery systems/adjuvants. It seems that PLGA and chitosan polymers are well-suited particles for the parenteral and non-parenteral administration of TB vaccines, respectively. Non-biodegradable synthetic polymers in comparison with biodegradable synthetic and natural polymers have been used less frequently. Therefore, further study on this category of polymers is required.

  14. Lipid-formulated bcg as an oral-bait vaccine for tuberculosis: vaccine stability, efficacy, and palatability to brushtail possums (Trichosurus vulpecula) in New Zealand.

    PubMed

    Cross, Martin L; Henderson, Ray J; Lambeth, Matthew R; Buddle, Bryce M; Aldwell, Frank E

    2009-07-01

    Bovine tuberculosis (Tb), due to infection with virulent Mycobacterium bovis, represents a threat to New Zealand agriculture due to vectorial transmission from wildlife reservoir species, principally the introduced Australian brushtail possum (Trichosurus vulpecula). An oral-delivery wildlife vaccine has been developed to immunize possums against Tb, based on formulation of the human Tb vaccine (M. bovis BCG) in edible lipid matrices. Here BCG bacilli were shown to be stable in lipid matrix formulation for over 8 mo in freezer storage, for 7 wk under room temperature conditions, and for 3-5 wk under field conditions in a forest/pasture margin habitat (when maintained in weatherproof bait-delivery sachets). Samples of the lipid matrix were flavored and offered to captive possums in a bait-preference study: a combination of 10% chocolate powder with anise oil was identified as the most effective attractant/palatability combination. In a replicated field study, 85-100% of wild possums were shown to access chocolate-flavored lipid pellets, when baits were applied to areas holding approximately 600-800 possums/km(2). Finally, in a controlled vaccination/challenge study, chocolate-flavored lipid vaccine samples containing 10(8) BCG bacilli were fed to captive possums, which were subsequently challenged via aerosol exposure to virulent M. bovis: vaccine immunogenicity was confirmed, and protection was identified by significantly reduced postchallenge weight loss in vaccinated animals compared to nonvaccinated controls. These studies indicate that, appropriately flavored, lipid delivery matrices may form effective bait vaccines for the control of Tb in wildlife.

  15. Tuberculosis Screening by Tuberculosis Skin Test or QuantiFERON®-TB Gold In-Tube Assay among an Immigrant Population with a High Prevalence of Tuberculosis and BCG Vaccination

    PubMed Central

    Painter, John A.; Graviss, Edward A.; Hai, Hoang Hoa; Nhung, Duong Thi Cam; Nga, Tran Thi Thanh; Ha, Ngan P.; Wall, Kirsten; Loan, Le Thien Huong; Parker, Matt; Manangan, Lilia; O’Brien, Rick; Maloney, Susan A.; Hoekstra, R. M.; Reves, Randall

    2013-01-01

    Rationale Each year 1 million persons acquire permanent U.S. residency visas after tuberculosis (TB) screening. Most applicants undergo a 2-stage screening with tuberculin skin test (TST) followed by CXR only if TST-positive at > 5 mm. Due to cross reaction with bacillus Calmette-Guérin (BCG), TST may yield false positive results in BCG-vaccinated persons. Interferon gamma release assays exclude antigens found in BCG. In Vietnam, like most high TB-prevalence countries, there is universal BCG vaccination at birth. Objectives 1. Compare the sensitivity of QuantiFERON ®-TB Gold In-Tube Assay (QFT) and TST for culture-positive pulmonary TB. 2. Compare the age-specific and overall prevalence of positive TST and QFT among applicants with normal and abnormal CXR. Methods We obtained TST and QFT results on 996 applicants with abnormal CXR, of whom 132 had TB, and 479 with normal CXR. Results The sensitivity for tuberculosis was 86.4% for QFT; 89.4%, 81.1%, and 52.3% for TST at 5, 10, and 15 mm. The estimated prevalence of positive results at age 15–19 years was 22% and 42% for QFT and TST at 10 mm, respectively. The prevalence increased thereafter by 0.7% year of age for TST and 2.1% for QFT, the latter being more consistent with the increase in TB among applicants. Conclusions During 2-stage screening, QFT is as sensitive as TST in detecting TB with fewer requiring CXR and being diagnosed with LTBI. These data support the use of QFT over TST in this population.  PMID:24367546

  16. The Effect of Oral Vaccination with Mycobacterium bovis BCG on the Development of Tuberculosis in Captive European Badgers (Meles meles).

    PubMed

    Chambers, Mark A; Aldwell, Frank; Williams, Gareth A; Palmer, Si; Gowtage, Sonya; Ashford, Roland; Dalley, Deanna J; Davé, Dipesh; Weyer, Ute; Salguero, Francisco J; Nunez, Alejandro; Nadian, Allan K; Crawshaw, Timothy; Corner, Leigh A L; Lesellier, Sandrine

    2017-01-01

    The European badger ( Meles meles ) is a reservoir host of Mycobacterium bovis and responsible for a proportion of the tuberculosis (TB) cases seen in cattle in the United Kingdom and Republic of Ireland. An injectable preparation of the bacillus Calmette-Guérin (BCG) vaccine is licensed for use in badgers in the UK and its use forms part of the bovine TB eradication plans of England and Wales. However, there are practical limitations to the widespread application of an injectable vaccine for badgers and a research priority is the development of an oral vaccine deliverable to badgers in bait. Previous studies reported the successful vaccination of badgers with oral preparations of 10 8 colony forming units (CFU) of both Pasteur and Danish strains of BCG contained within a lipid matrix composed of triglycerides of fatty acids. Protection against TB in these studies was expressed as a reduction in the number and apparent progression of visible lesions, and reductions in the bacterial load and dissemination of infection. To reduce the cost of an oral vaccine and reduce the potential for environmental contamination with BCG, it is necessary to define the minimal efficacious dose of oral BCG for badgers. The objectives of the two studies reported here were to compare the efficacy of BCG Danish strain in a lipid matrix with unformulated BCG given orally, and to evaluate the efficacy of BCG Danish in a lipid matrix at a 10-fold lower dose than previously evaluated in badgers. In the first study, both BCG unformulated and in a lipid matrix reduced the number and apparent progression of visible lesions and the dissemination of infection from the lung. In the second study, vaccination with BCG in the lipid matrix at a 10-fold lower dose produced a similar outcome, but with greater intra-group variability than seen with the higher dose in the first study. Further research is needed before we are able to recommend a final dose of BCG for oral vaccination of badgers against TB

  17. The Effect of Oral Vaccination with Mycobacterium bovis BCG on the Development of Tuberculosis in Captive European Badgers (Meles meles)

    PubMed Central

    Chambers, Mark A.; Aldwell, Frank; Williams, Gareth A.; Palmer, Si; Gowtage, Sonya; Ashford, Roland; Dalley, Deanna J.; Davé, Dipesh; Weyer, Ute; Salguero, Francisco J.; Nunez, Alejandro; Nadian, Allan K.; Crawshaw, Timothy; Corner, Leigh A. L.; Lesellier, Sandrine

    2017-01-01

    The European badger (Meles meles) is a reservoir host of Mycobacterium bovis and responsible for a proportion of the tuberculosis (TB) cases seen in cattle in the United Kingdom and Republic of Ireland. An injectable preparation of the bacillus Calmette-Guérin (BCG) vaccine is licensed for use in badgers in the UK and its use forms part of the bovine TB eradication plans of England and Wales. However, there are practical limitations to the widespread application of an injectable vaccine for badgers and a research priority is the development of an oral vaccine deliverable to badgers in bait. Previous studies reported the successful vaccination of badgers with oral preparations of 108 colony forming units (CFU) of both Pasteur and Danish strains of BCG contained within a lipid matrix composed of triglycerides of fatty acids. Protection against TB in these studies was expressed as a reduction in the number and apparent progression of visible lesions, and reductions in the bacterial load and dissemination of infection. To reduce the cost of an oral vaccine and reduce the potential for environmental contamination with BCG, it is necessary to define the minimal efficacious dose of oral BCG for badgers. The objectives of the two studies reported here were to compare the efficacy of BCG Danish strain in a lipid matrix with unformulated BCG given orally, and to evaluate the efficacy of BCG Danish in a lipid matrix at a 10-fold lower dose than previously evaluated in badgers. In the first study, both BCG unformulated and in a lipid matrix reduced the number and apparent progression of visible lesions and the dissemination of infection from the lung. In the second study, vaccination with BCG in the lipid matrix at a 10-fold lower dose produced a similar outcome, but with greater intra-group variability than seen with the higher dose in the first study. Further research is needed before we are able to recommend a final dose of BCG for oral vaccination of badgers against TB or

  18. A novel vaccine p846 encoding Rv3615c, Mtb10.4, and Rv2660c elicits robust immune response and alleviates lung injury induced by Mycobacterium infection.

    PubMed

    Kong, Hongmei; Dong, Chunsheng; Xiong, Sidong

    2014-01-01

    Development of effective anti-tuberculosis (TB) vaccines is one of the important steps to improve control of TB. Cell-mediated immune response significantly affects the control of M. tuberculosis infection. Thus, vaccines able to elicit strong cellular immune response hold special advantages against TB. In this study, three well-defined mycobacterial antigens (Rv3615c, Mtb10.4 [Rv0228], and Rv2660c) were engineered as a novel triple-antigen fusion DNA vaccine p846. The p846 vaccine consists of a high density of CD4(+) and CD8(+) T-cell epitopes. Intramuscular immunization of p846 induced robust T cells mediated immune response comparable to that of bacillus Calmette-Guérin (BCG) vaccination but more effective than that of individual antigen vaccination. After mycobacterial challenge, p846 immunization decreased bacterial burden at least 15-fold compared with individual antigen-based vaccination. Notably, the lungs of mice immunized with p846 exhibited fewer inflammatory cell infiltrates and less damage than those of control group mice. Our data demonstrate that the potential of p846 vaccine to protect against TB and the feasibility of this design strategy for further TB vaccine development.

  19. Impact and cost-effectiveness of new tuberculosis vaccines in low- and middle-income countries

    PubMed Central

    Knight, Gwenan M.; Griffiths, Ulla K.; Sumner, Tom; Laurence, Yoko V.; Gheorghe, Adrian; Vassall, Anna; Glaziou, Philippe; White, Richard G.

    2014-01-01

    To help reach the target of tuberculosis (TB) disease elimination by 2050, vaccine development needs to occur now. We estimated the impact and cost-effectiveness of potential TB vaccines in low- and middle-income countries using an age-structured transmission model. New vaccines were assumed to be available in 2024, to prevent active TB in all individuals, to have a 5-y to lifetime duration of protection, to have 40–80% efficacy, and to be targeted at “infants” or “adolescents/adults.” Vaccine prices were tiered by income group (US $1.50–$10 per dose), and cost-effectiveness was assessed using incremental cost per disability adjusted life year (DALY) averted compared against gross national income per capita. Our results suggest that over 2024–2050, a vaccine targeted to adolescents/adults could have a greater impact than one targeted at infants. In low-income countries, a vaccine with a 10-y duration and 60% efficacy targeted at adolescents/adults could prevent 17 (95% range: 11–24) million TB cases by 2050 and could be considered cost-effective at $149 (cost saving to $387) per DALY averted. If targeted at infants, 0.89 (0.42–1.58) million TB cases could be prevented at $1,692 ($634–$4,603) per DALY averted. This profile targeted at adolescents/adults could be cost-effective at $4, $9, and $20 per dose in low-, lower-middle–, and upper-middle–income countries, respectively. Increased investments in adult-targeted TB vaccines may be warranted, even if only short duration and low efficacy vaccines are likely to be feasible, and trials among adults should be powered to detect low efficacies. PMID:25288770

  20. In silico design of Mycobacterium tuberculosis epitope ensemble vaccines.

    PubMed

    Shah, Preksha; Mistry, Jaymisha; Reche, Pedro A; Gatherer, Derek; Flower, Darren R

    2018-05-01

    Effective control of Mycobacterium tuberculosis is a global necessity. In 2015, tuberculosis (TB) caused more deaths than HIV. Considering the increasing prevalence of multi-drug resistant forms of M. tuberculosis, the need for effective TB vaccines becomes imperative. Currently, the only licensed TB vaccine is Bacillus Calmette-Guérin (BCG). Yet, BCG has many drawbacks limiting its efficacy and applicability. We applied advanced computational procedures to derive a universal TB vaccine and one targeting East Africa. Our approach selects an optimal set of highly conserved, experimentally validated epitopes, with high projected population coverage (PPC). Through rigorous data analysis, five different potential vaccine combinations were selected each with PPC above 80% for East Africa and above 90% for the World. Two potential vaccines only contained CD8+ epitopes, while the others included both CD4+ and CD8+ epitopes. Our prime vaccine candidate was a putative seven-epitope ensemble comprising: SRGWSLIKSVRLGNA, KPRIITLTMNPALDI, AAHKGLMNIALAISA, FPAGGSTGSL, MLLAVTVSL, QSSFYSDW and KMRCGAPRY, with a 97.4% global PPC and a 92.7% East African PPC. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Field evaluation of the efficacy of Mycobacterium bovis BCG vaccine against tuberculosis in goats.

    PubMed

    Vidal, Enric; Arrieta-Villegas, Claudia; Grasa, Miriam; Mercader, Irene; Domingo, Mariano; Pérez de Val, Bernat

    2017-08-17

    Control of animal tuberculosis (TB) through vaccination has emerged as a long-term strategy to complement test and slaughter control strategy. A pilot trial under field conditions was conducted in a goat herd with high TB prevalence to assess the efficacy of the Mycobacterium bovis BCG vaccine. Twenty-three goat kids vaccinated with BCG and other 22 unvaccinated control kids were euthanized at 18 months post-vaccination. Gross pathological and histopathological examination of target tissues was performed for detection of tuberculous lesions and assessment of vaccine efficacy. Mycobacterial culture and DNA detection were used to confirm Mycobacterium caprae infection. Vaccination significantly reduced the number of animals with TB lesions compared to unvaccinated controls (35% and 77%, respectively; P < 0.01). This reduction was even higher if only extra-pulmonary infection was considered (17% and 68%, respectively; P < 0.001). This trial demonstrates that BCG vaccination of goats can significantly reduce the TB lesion rates in high disease exposure conditions, indicating that vaccination could contribute to the control of TB in domestic goats.

  2. Host responses to mycobacterial infections: Spotlight on biomarker discovery to predict vaccine

    USDA-ARS?s Scientific Manuscript database

    The global spread of tuberculosis (TB) in animals and humans result in enormous economic. social and public health burdens. TB vaccine development in both humans and animals has produced a growing portfolio of candidates with potential applicability across species. However, the lack of understandin...

  3. Enhanced Immune Response and Protective Effects of Nano-chitosan-based DNA Vaccine Encoding T Cell Epitopes of Esat-6 and FL against Mycobacterium Tuberculosis Infection

    PubMed Central

    Feng, Ganzhu; Jiang, Qingtao; Xia, Mei; Lu, Yanlai; Qiu, Wen; Zhao, Dan; Lu, Liwei; Peng, Guangyong; Wang, Yingwei

    2013-01-01

    Development of a novel and effective vaccine against Mycobacterium tuberculosis (M.tb) is a challenging for preventing TB infection. In this study, a novel nanoparticle-based recombinant DNA vaccine was developed, which contains Esat-6 three T cell epitopes (Esat-6/3e) and fms-like tyrosine kinase 3 ligand (FL) genes (termed Esat-6/3e-FL), and was enveloped with chitosan (CS) nanoparticles (nano-chitosan). The immunologic and protective efficacy of the nano-chitosan-based DNA vaccine (termed nano-Esat-6/3e-FL) was assessed in C57BL/6 mice after intramuscular prime vaccination with the plasmids DNA and nasal boost with the Esat-6/3e peptides. The results showed that the immunized mice remarkably elicited enhanced T cell responses and protection against M.tb H37Rv challenge. These findings indicate that the nano-chitosan can significantly elevate the immunologic and protective effects of the DNA vaccine, and the nano-Esat-6/3e-FL is a useful vaccine for preventing M.tb infection in mice. PMID:23637790

  4. Novel licensure pathways for expeditious introduction of new tuberculosis vaccines: a discussion of the adaptive licensure concept.

    PubMed

    Rustomjee, Roxana; Lockhart, Stephen; Shea, Jacqueline; Fourie, P Bernard; Hindle, Zoë; Steel, Gavin; Hussey, Gregory; Ginsberg, Ann; Brennan, Michael J

    2014-03-01

    The ultimate goal of vaccine development is licensure of a safe and efficacious product that has a well-defined manufacturing process resulting in a high quality product. In general, clinical development and regulatory approval occurs in a linear, sequential manner: Phase 1 - safety, immunogenicity; Phase 2 - immunogenicity, safety, dose ranging and preliminary efficacy; Phase 3 - definitive efficacy, safety, lot consistency; and, following regulatory approval, Phase 4 - post-marketing safety and effectiveness. For candidate TB vaccines, where correlates of protection are not yet identified, phase 2 and 3 efficacy of disease prevention trials are, by necessity, very large. Each trial would span 2-5 years, with full licensure expected only after 1 or even 2 decades of development. Given the urgent unmet need for a new TB vaccine, a satellite discussion was held at the International African Vaccinology Conference in Cape Town, South Africa in November 2012, to explore the possibility of expediting licensure by use of an "adaptive licensure" process, based on a risk/benefit assessment that is specific to regional needs informed by epidemiology. This may be appropriate for diseases such as TB, where high rates of morbidity, mortality, particularly in high disease burden countries, impose an urgent need for disease prevention. The discussion focused on two contexts: licensure within the South African regulatory environment - a high burden country where TB vaccine efficacy trials are on-going, and licensure by the United States FDA --a well-resourced regulatory agency where approval could facilitate global licensure of a novel TB vaccine. Copyright © 2013. Published by Elsevier Ltd.

  5. Differential Adverse Event Profiles Associated with BCG as a Preventive Tuberculosis Vaccine or Therapeutic Bladder Cancer Vaccine Identified by Comparative Ontology-Based VAERS and Literature Meta-Analysis

    PubMed Central

    Xie, Jiangan; Codd, Christopher; Mo, Kevin; He, Yongqun

    2016-01-01

    M. bovis strain Bacillus Calmette–Guérin (BCG) has been the only licensed live attenuated vaccine against tuberculosis (TB) for nearly one century and has also been approved as a therapeutic vaccine for bladder cancer treatment since 1990. During its long time usage, different adverse events (AEs) have been reported. However, the AEs associated with the BCG preventive TB vaccine and therapeutic cancer vaccine have not been systematically compared. In this study, we systematically collected various BCG AE data mined from the US VAERS database and PubMed literature reports, identified statistically significant BCG-associated AEs, and ontologically classified and compared these AEs related to these two types of BCG vaccine. From 397 VAERS BCG AE case reports, we identified 64 AEs statistically significantly associated with the BCG TB vaccine and 14 AEs with the BCG cancer vaccine. Our meta-analysis of 41 peer-reviewed journal reports identified 48 AEs associated with the BCG TB vaccine and 43 AEs associated with the BCG cancer vaccine. Among all identified AEs from VAERS and literature reports, 25 AEs belong to serious AEs. The Ontology of Adverse Events (OAE)-based ontological hierarchical analysis indicated that the AEs associated with the BCG TB vaccine were enriched in immune system (e.g., lymphadenopathy and lymphadenitis), skin (e.g., skin ulceration and cyanosis), and respiratory system (e.g., cough and pneumonia); in contrast, the AEs associated with the BCG cancer vaccine mainly occurred in the urinary system (e.g., dysuria, pollakiuria, and hematuria). With these distinct AE profiles detected, this study also discovered three AEs (i.e., chills, pneumonia, and C-reactive protein increased) shared by the BCG TB vaccine and bladder cancer vaccine. Furthermore, our deep investigation of 24 BCG-associated death cases from VAERS identified the important effects of age, vaccine co-administration, and immunosuppressive status on the final BCG-associated death

  6. Mucosal BCG Vaccination Induces Protective Lung-Resident Memory T Cell Populations against Tuberculosis

    PubMed Central

    Perdomo, Carolina; Zedler, Ulrike; Kühl, Anja A.; Lozza, Laura; Saikali, Philippe; Sander, Leif E.; Vogelzang, Alexis; Kupz, Andreas

    2016-01-01

    ABSTRACT Mycobacterium bovis Bacille Calmette-Guérin (BCG) is the only licensed vaccine against tuberculosis (TB), yet its moderate efficacy against pulmonary TB calls for improved vaccination strategies. Mucosal BCG vaccination generates superior protection against TB in animal models; however, the mechanisms of protection remain elusive. Tissue-resident memory T (TRM) cells have been implicated in protective immune responses against viral infections, but the role of TRM cells following mycobacterial infection is unknown. Using a mouse model of TB, we compared protection and lung cellular infiltrates of parenteral and mucosal BCG vaccination. Adoptive transfer and gene expression analyses of lung airway cells were performed to determine the protective capacities and phenotypes of different memory T cell subsets. In comparison to subcutaneous vaccination, intratracheal and intranasal BCG vaccination generated T effector memory and TRM cells in the lung, as defined by surface marker phenotype. Adoptive mucosal transfer of these airway-resident memory T cells into naive mice mediated protection against TB. Whereas airway-resident memory CD4+ T cells displayed a mixture of effector and regulatory phenotype, airway-resident memory CD8+ T cells displayed prototypical TRM features. Our data demonstrate a key role for mucosal vaccination-induced airway-resident T cells in the host defense against pulmonary TB. These results have direct implications for the design of refined vaccination strategies. PMID:27879332

  7. The Progress of Therapeutic Vaccination with Regard to Tuberculosis.

    PubMed

    Cardona, Pere-Joan

    2016-01-01

    A major problem with tuberculosis (TB) control is the long duration of drug therapy-both for latent and for active TB. Therapeutic vaccination has been postulated to improve this situation, and to this end there are several candidates already in clinical phases of development. These candidates follow two main designs, namely bacilli-directed therapy based on inactivated -whole or -fragmented bacillus ( Mycobacterium w and RUTI) or fusion proteins that integrate non-replicating bacilli -related antigens (H56 vaccine), and host-directed therapy to reduce the tissue destruction. The administration of inactivated Mycobacterium vaccae prevents the "Koch phenomenon" response, and oral administration of heat-killed Mycobacterium manresensis prevents excessive neutrophilic infiltration of the lesions. This review also tries to explain the success of Mycobacterium tuberculosis by reviewing its evolution from infection to disease, and highlights the lack of a definitive understanding of the natural history of TB pathology and the need to improve our knowledge on TB immunology and pathogenesis.

  8. The Progress of Therapeutic Vaccination with Regard to Tuberculosis

    PubMed Central

    Cardona, Pere-Joan

    2016-01-01

    A major problem with tuberculosis (TB) control is the long duration of drug therapy–both for latent and for active TB. Therapeutic vaccination has been postulated to improve this situation, and to this end there are several candidates already in clinical phases of development. These candidates follow two main designs, namely bacilli-directed therapy based on inactivated -whole or -fragmented bacillus (Mycobacterium w and RUTI) or fusion proteins that integrate non-replicating bacilli -related antigens (H56 vaccine), and host-directed therapy to reduce the tissue destruction. The administration of inactivated Mycobacterium vaccae prevents the “Koch phenomenon” response, and oral administration of heat-killed Mycobacterium manresensis prevents excessive neutrophilic infiltration of the lesions. This review also tries to explain the success of Mycobacterium tuberculosis by reviewing its evolution from infection to disease, and highlights the lack of a definitive understanding of the natural history of TB pathology and the need to improve our knowledge on TB immunology and pathogenesis. PMID:27733848

  9. Baculovirus-vectored multistage Plasmodium vivax vaccine induces both protective and transmission-blocking immunities against transgenic rodent malaria parasites.

    PubMed

    Mizutani, Masanori; Iyori, Mitsuhiro; Blagborough, Andrew M; Fukumoto, Shinya; Funatsu, Tomohiro; Sinden, Robert E; Yoshida, Shigeto

    2014-10-01

    A multistage malaria vaccine targeting the pre-erythrocytic and sexual stages of Plasmodium could effectively protect individuals against infection from mosquito bites and provide transmission-blocking (TB) activity against the sexual stages of the parasite, respectively. This strategy could help prevent malaria infections in individuals and, on a larger scale, prevent malaria transmission in communities of endemicity. Here, we describe the development of a multistage Plasmodium vivax vaccine which simultaneously expresses P. vivax circumsporozoite protein (PvCSP) and P25 (Pvs25) protein of this species as a fusion protein, thereby acting as a pre-erythrocytic vaccine and a TB vaccine, respectively. A new-concept vaccine platform based on the baculovirus dual-expression system (BDES) was evaluated. The BDES-Pvs25-PvCSP vaccine displayed correct folding of the Pvs25-PvCSP fusion protein on the viral envelope and was highly expressed upon transduction of mammalian cells in vitro. This vaccine induced high levels of antibodies to Pvs25 and PvCSP and elicited protective (43%) and TB (82%) efficacies against transgenic P. berghei parasites expressing the corresponding P. vivax antigens in mice. Our data indicate that our BDES, which functions as both a subunit and DNA vaccine, can offer a promising multistage vaccine capable of delivering a potent antimalarial pre-erythrocytic and TB response via a single immunization regimen. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  10. Taking aim at novel vaccines market.

    PubMed

    Awasthi, Sita

    2009-10-01

    The World Vaccine Congress Washington 2009 was held in Chantilly, VA USA April 2O -23rd. The Vaccine congress attracted over 400 participants from across the world, including leading vaccine manufacturers, biotechs, governmental agencies, NGOs, research and academic institutes, venture capital and legal firms, contract service and equipment manufacturers. The speakers covered a wide range of topics, including the role of government and regulatory agencies, funding availability, research and development, manufacturing, packaging and post vaccine evaluations. Past vaccine development efforts have historically focused on infectious diseases. With advancements in the field of immunology, molecular biology and vaccinology, the vaccine field has begun moving in new directions. "Taking aim at novel vaccines market" session chaired by Dr. Una Ryan, Chief Executive Officer of Waltham Technologies, was focused on traditional approaches to novel targets (nosocomial infections), novel approaches to traditional targets (flu and rabies), novel approaches to novel targets (Type 1 diabetes, multiple sclerosis and smoking) and vaccines for developing markets (TB, malaria, rabies). The importance of collaborations among academic institutions, industries, and philanthropic foundations for developing markets was also emphasized.

  11. Tuberculosis vaccine candidate: Characterization of H4-IC31 formulation and H4 antigen conformation.

    PubMed

    Deshmukh, Sasmit S; Magcalas, Federico Webster; Kalbfleisch, Kristen N; Carpick, Bruce W; Kirkitadze, Marina D

    2018-08-05

    Tuberculosis (TB) is one of the leading causes of death worldwide, making the development of effective TB vaccines a global priority. A TB vaccine consisting of a recombinant fusion protein, H4, combined with a novel synthetic cationic adjuvant, IC31 ® , is currently being developed. The H4 fusion protein consists of two immunogenic mycobacterial antigens, Ag85 B and TB10.4, and the IC31 ® adjuvant is a mixture of KLK, a leucine-rich peptide (KLKL5KLK), and the oligodeoxynucleotide ODN1a, a TLR9 ligand. However, efficient and robust methods for assessing these formulated components are lacking. Here, we developed and optimized phase analysis light scattering (PALS), electrical sensing zone (ESZ), and Raman, FTIR, and CD spectroscopy methods to characterize the H4-IC31 vaccine formulation. PALS-measured conductivity and zeta potential values could differentiate between the similarly sized particles of IC31 ® adjuvant and the H4-IC31 vaccine candidate and could thereby serve as a control during vaccine formulation. In addition, zeta potential is indicative of the adjuvant to antigen ratio which is the key in the immunomodulatory response of the vaccine. ESZ was used as an orthogonal method to measure IC31 ® and H4-IC31 particle sizes. Raman, FTIR, and CD spectroscopy revealed structural changes in H4 protein and IC31 ® adjuvant, inducing an increase in both the β-sheet and random coil content as a result of adsorption. Furthermore, nanoDSF showed changes in the tertiary structure of H4 protein as a result of adjuvantation to IC31 ® . Our findings demonstrate the applicability of biophysical methods to characterize vaccine components in the final H4-IC31 drug product without the requirement for desorption. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Fused Mycobacterium tuberculosis multi-stage immunogens with an Fc-delivery system as a promising approach for the development of a tuberculosis vaccine.

    PubMed

    Mosavat, Arman; Soleimanpour, Saman; Farsiani, Hadi; Sadeghian, Hamid; Ghazvini, Kiarash; Sankian, Mojtaba; Jamehdar, Saeid Amel; Rezaee, Seyed Abdolrahim

    2016-04-01

    Tuberculosis (TB) remains a major health problem worldwide. Currently, the Bacilli Calmette-Guérin (BCG) is the only available licensed TB vaccine, which has low efficacy in protection against adult pulmonary TB. Therefore, the development of a safe and effective vaccine against TB needs global attention. In the present study, a novel multi-stage subunit vaccine candidate from culture filtrate protein-10 (CFP-10) and heat shock protein X (HspX) of Mycobacterium tuberculosis fused to the Fc domain of mouse IgG2a as a selective delivery system for antigen-presenting cells (APCs) was produced and its immunogenicity assessed. The optimized gene constructs were introduced into pPICZαA expression vectors, and the resultant plasmids (pPICZαA-CFP-10:Hspx:Fcγ2a and pPICZαA-CFP-10:Hspx:His) were transferred into Pichia pastoris by electroporation. The identification of both purified recombinant fusion proteins was evaluated by SDS-PAGE and immunoblotting. Then the immunogenicity of the recombinant proteins with and without BCG was evaluated in BALB/c mice by assessing the level of IFN-γ, IL-12, IL-4, IL-17 and TGF-β cytokines. Both multi-stage vaccines (CFP-10:HspX:Fcγ2a and CFP-10:HspX:His) induced Th1-type cellular responses by producing high level of IFN-γ (272 pg/mL, p<0.001) and IL-12 (191 pg/mL, p<0.001). However, the Fc-tagged recombinant protein induced more effective Th1-type cellular responses with a low level of IL-4 (10 pg/mL) compared to the CFP-10:HspX:His group. The production of IFN-γ to CFP-10:HspX:Fcγ2a was markedly consistent and showed an increasing trend for IL-12 compared with the BCG or CFP-10:HspX:His primed and boosted groups. Findings revealed that CFP-10:Hspx:Fcγ2a fusion protein can elicit strong Th1 antigen-specific immune responses in favor of protective immunity in mice and could provide new insight for introducing an effective multi-stage subunit vaccine against TB. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Efficacy of parenteral vaccination against tuberculosis with heat-inactivated Mycobacterium bovis in experimentally challenged goats.

    PubMed

    Arrieta-Villegas, Claudia; Perálvarez, Tania; Vidal, Enric; Puighibet, Zoë; Moll, Xavier; Canturri, Albert; Sevilla, Iker A; Espada, Yvonne; Juste, Ramón A; Domingo, Mariano; Pérez de Val, Bernat

    2018-01-01

    Tuberculosis (TB) in animals is a re-emerging disease with a wide range of hosts that causes large economic losses in livestock. Goats are particularly susceptible to TB and, in endemic areas, vaccination may be a valuable measure to control the disease. The main aim of this study was to evaluate the efficacy of parenteral vaccination of goats with a heat-inactivated Mycobacterium bovis (HIMB) vaccine, and compare it to M. bovis Bacille Calmette-Guérin (BCG) vaccine. Twenty-four goat kids were divided in 3 groups as following: HIMB vaccinated group (n = 8), BCG vaccinated group (n = 8) and unvaccinated group (n = 8). Afterwards, goats were experimentally challenged with Mycobacterium caprae by the endobronchial route. Antigen specific interferon-γ release assays and serology were performed after vaccination and challenge. Pathological and bacteriological parameters were evaluated after necropsy at 9 weeks post-challenge (p.c.). HIMB vaccine showed similar levels of protection to BCG in terms of volume reduction of thoracic TB lesions, presence of extra-pulmonary lesions, as well as a slight reduction of bacterial load in pulmonary lymph nodes. Moreover, HIMB vaccine did not induce interferences on the interferon-γ release assay based on reagents previously developed to differentiate infected from BCG vaccinated individuals. The results indicate that HIMB is a suitable vaccine candidate for further larger-scale trials under field conditions in goats.

  14. Malaria Infections Do Not Compromise Vaccine-Induced Immunity against Tuberculosis in Mice

    PubMed Central

    Parra, Marcela; Derrick, Steven C.; Yang, Amy; Tian, JinHua; Kolibab, Kristopher; Oakley, Miranda; Perera, Liyanage P.; Jacobs, William R.; Kumar, Sanjai; Morris, Sheldon L.

    2011-01-01

    Background Given the considerable geographic overlap in the endemic regions for malaria and tuberculosis, it is probable that co-infections with Mycobacterium tuberculosis and Plasmodium species are prevalent. Thus, it is quite likely that both malaria and TB vaccines may be used in the same populations in endemic areas. While novel vaccines are currently being developed and tested individually against each of these pathogens, the efficacy of these vaccines has not been evaluated in co-infection models. To further assess the effectiveness of these new immunization strategies, we investigated whether co-infection with malaria would impact the anti-tuberculosis protection induced by four different types of TB vaccines in a mouse model of pulmonary tuberculosis. Principal Findings Here we show that the anti-tuberculosis protective immunity induced by four different tuberculosis vaccines was not impacted by a concurrent infection with Plasmodium yoelii NL, a nonlethal form of murine malaria. After an aerogenic challenge with virulent M. tuberculosis, the lung bacterial burdens of vaccinated animals were not statistically different in malaria infected and malaria naïve mice. Multi-parameter flow cytometric analysis showed that the frequency and the median fluorescence intensities (MFI) for specific multifunctional T (MFT) cells expressing IFN-γ, TNF-α, and/or IL-2 were suppressed by the presence of malaria parasites at 2 weeks following the malaria infection but was not affected after parasite clearance at 7 and 10 weeks post-challenge with P. yoelii NL. Conclusions Our data indicate that the effectiveness of novel TB vaccines in protecting against tuberculosis was unaffected by a primary malaria co-infection in a mouse model of pulmonary tuberculosis. While the activities of specific MFT cell subsets were reduced at elevated levels of malaria parasitemia, the T cell suppression was short-lived. Our findings have important relevance in developing strategies for the

  15. Bacillus Calmette-Guérin Vaccination Using a Microneedle Patch

    PubMed Central

    Hiraishi, Yasuhiro; Nandakumar, Subhadra; Choi, Seong-O; Lee, Jeong Woo; Kim, Yeu-Chun; Posey, James E.; Sable, Suraj B.; Prausnitz, Mark R.

    2011-01-01

    Tuberculosis (TB) caused by Mycobacterium tuberculosis continues to be a leading cause of mortality among bacterial diseases, and the bacillus Calmette-Guerin (BCG) is the only licensed vaccine for human use against this disease. TB prevention and control would benefit from an improved method of BCG vaccination that simplifies logistics and eliminates dangers posed by hypodermic needles without compromising immunogenicity. Here, we report the design and engineering of a BCG-coated microneedle vaccine patch for a simple and improved intradermal delivery of the vaccine. The microneedle vaccine patch induced a robust cell-mediated immune response in both the lungs and spleen of guinea pigs. The response was comparable to the traditional hypodermic needle based intradermal BCG vaccination and was characterized by a strong antigen specific lymphocyte proliferation and IFN-γ levels with high frequencies of CD4+IFN-γ+, CD4+TNF-α+ and CD4+IFN-γ+TNF-α+ T cells. The BCG-coated microneedle vaccine patch was highly immunogenic in guinea pigs and supports further exploration of this new technology as a simpler, safer, and compliant vaccination that could facilitate increased coverage, especially in developing countries that lack adequate healthcare infrastructure. PMID:21277407

  16. Recent mouse models and vaccine candidates for preventing chronic/latent tuberculosis infection and its reactivation.

    PubMed

    Pedroza-Roldán, César; Flores-Valdez, Mario Alberto

    2017-08-31

    Tuberculosis (TB) remains a major challenge in public health worldwide. Until today, the only widely used and approved vaccine is the Mycobacterium bovis bacille Calmette-Guerin (BCG). This vaccine provides a highly variable level of protection against the active, pulmonary form of tuberculosis, and practically none against the latent form of TB infection. This disparity in protection has been extensively studied, and for this reason, several groups have focused their research on the quest for attenuated vaccines based on M. tuberculosis or on the identification of latency-associated antigens that can be incorporated into modified BCG, or that can be used as adjuvanted subunit vaccines. In order to seek new potential antigens relevant for infection, some researchers have performed experiments with highly sensitive techniques such as transcriptomic and proteomic analyses using sputum samples from humans or by using mouse models resembling several aspects of TB. In this review, we focus on reports of new mouse models or mycobacterial antigens recently tested for developing vaccine candidates against chronic/latent tuberculosis and its reactivation.

  17. Enhanced effect of BCG vaccine against pulmonary Mycobacterium tuberculosis infection in mice with lung Th17 response to mycobacterial heparin-binding hemagglutinin adhesin antigen.

    PubMed

    Fukui, Masayuki; Shinjo, Kikuko; Umemura, Masayuki; Shigeno, Satoko; Harakuni, Tetsuya; Arakawa, Takeshi; Matsuzaki, Goro

    2015-12-01

    Although the BCG vaccine can prevent tuberculosis (TB) in infants, its ability to prevent adult pulmonary TB is reportedly limited. Therefore, development of a novel effective vaccine against pulmonary TB has become an international research priority. We have previously reported that intranasal vaccination of mice with a mycobacterial heparin-binding hemagglutinin adhesin (HBHA) plus mucosal adjuvant cholera toxin (CT) enhances production of IFN-γ and anti-HBHA antibody and suppresses extrapulmonary bacterial dissemination after intranasal infection with BCG. In the present study, the effects of intranasal HBHA + CT vaccine on murine pulmonary Mycobacterium tuberculosis (Mtb) infection were examined. Intranasal HBHA + CT vaccination alone failed to reduce the bacterial burden in the infected lung. However, a combination vaccine consisting of s.c. BCG priming and an intranasal HBHA + CT booster significantly enhanced protective immunity against pulmonary Mtb infection on day 14 compared with BCG vaccine alone. Further, it was found that intranasal HBHA + CT vaccine enhanced not only IFN-γ but also IL-17A production by HBHA-specific T cells in the lung after pulmonary Mtb infection. Therefore, this combination vaccine may be a good candidate for a new vaccine strategy against pulmonary TB. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  18. Vaccines for the 21st century

    PubMed Central

    Delany, Isabel; Rappuoli, Rino; De Gregorio, Ennio

    2014-01-01

    In the last century, vaccination has been the most effective medical intervention to reduce death and morbidity caused by infectious diseases. It is believed that vaccines save at least 2–3 million lives per year worldwide. Smallpox has been eradicated and polio has almost disappeared worldwide through global vaccine campaigns. Most of the viral and bacterial infections that traditionally affected children have been drastically reduced thanks to national immunization programs in developed countries. However, many diseases are not yet preventable by vaccination, and vaccines have not been fully exploited for target populations such as elderly and pregnant women. This review focuses on the state of the art of recent clinical trials of vaccines for major unmet medical needs such as HIV, malaria, TB, and cancer. In addition, we describe the innovative technologies currently used in vaccine research and development including adjuvants, vectors, nucleic acid vaccines, and structure-based antigen design. The hope is that thanks to these technologies, more diseases will be addressed in the 21st century by novel preventative and therapeutic vaccines. PMID:24803000

  19. European Vaccine Initiative: lessons from developing malaria vaccines.

    PubMed

    Geels, Mark J; Imoukhuede, Egeruan B; Imbault, Nathalie; van Schooten, Harry; McWade, Terry; Troye-Blomberg, Marita; Dobbelaer, Roland; Craig, Alister G; Leroy, Odile

    2011-12-01

    For over 10 years, the European Vaccine Initiative (EVI; European Malaria Vaccine Initiative until 2009) has contributed to the development of 24 malaria candidate vaccine antigens with 13 vaccine candidates being advanced into Phase I clinical trials, two of which have been transitioned for further clinical development in sub-Saharan Africa. Since its inception the EVI organization has operated as a funding agency, but with a clear service-oriented strategy. The scientific successes and difficulties encountered during these years and how these efforts have led to standardization and harmonization in vaccine development through large-scale European consortia are discussed. In the future, the EVI will remain instrumental in the pharmaceutical and clinical development of vaccines against 'diseases of poverty' with a continued focus on malaria. EVI will continue to focus on funding and managing preclinical evaluation up to Phase I/II clinical trials and strengthening the vaccine-development infrastructure in Europe, albeit with a global orientation.

  20. Initial lessons from public-private partnerships in drug and vaccine development.

    PubMed Central

    Wheeler, C.; Berkley, S.

    2001-01-01

    In recent years, venture capital approaches have delivered impressive results in identifying and funding promising health discoveries and bringing them to market. This success has inspired public sector experiments with "social venture capital" approaches to address the dearth of affordable treatment and prevention for diseases of the developing world. Employing the same focus on well-defined and measurable objectives, and the same type of connections to pool and deploy resources as their for-profit counterparts, social venture capitalists seek to use the tools and incentives of capitalism to solve one of its biggest failures: the lack of drugs and vaccines for diseases endemic to low-income populations. As part of a larger trend of partnerships emerging in health product donation and distribution, public-private partnerships for pharmaceutical development have led research and development (R&D) efforts to generate more accessible and efficacious products for diseases such as malaria, tuberculosis, and AIDS. In this article, three R&D-focused partnerships are explored: the International AIDS Vaccine Initiative; the Medicines for Malaria Venture; and the newly formed Global Alliance for TB Drug Development. The article highlights key elements essential to the success of these ventures. PMID:11545329

  1. Digital health for the End TB Strategy: developing priority products and making them work

    PubMed Central

    Timimi, Hazim; Kurosinski, Pascal; Migliori, Giovanni Battista; Van Gemert, Wayne; Denkinger, Claudia; Isaacs, Chris; Story, Alistair; Garfein, Richard S.; do Valle Bastos, Luis Gustavo; Yassin, Mohammed A.; Rusovich, Valiantsin; Skrahina, Alena; Van Hoi, Le; Broger, Tobias; Abubakar, Ibrahim; Hayward, Andrew; Thomas, Bruce V.; Temesgen, Zelalem; Quraishi, Subhi; von Delft, Dalene; Jaramillo, Ernesto; Weyer, Karin; Raviglione, Mario C.

    2016-01-01

    In 2014, the World Health Organization (WHO) developed the End TB Strategy in response to a World Health Assembly Resolution requesting Member States to end the worldwide epidemic of tuberculosis (TB) by 2035. For the strategy's objectives to be realised, the next 20 years will need novel solutions to address the challenges posed by TB to health professionals, and to affected people and communities. Information and communication technology presents opportunities for innovative approaches to support TB efforts in patient care, surveillance, programme management and electronic learning. The effective application of digital health products at a large scale and their continued development need the engagement of TB patients and their caregivers, innovators, funders, policy-makers, advocacy groups, and affected communities. In April 2015, WHO established its Global Task Force on Digital Health for TB to advocate and support the development of digital health innovations in global efforts to improve TB care and prevention. We outline the group's approach to stewarding this process in alignment with the three pillars of the End TB Strategy. The supplementary material of this article includes target product profiles, as developed by early 2016, defining nine priority digital health concepts and products that are strategically positioned to enhance TB action at the country level. PMID:27230443

  2. Tuberculin skin testing and T-SPOT.TB in internationally adopted children.

    PubMed

    Spicer, Kevin B; Turner, Joanne; Wang, Shu-Hua; Koranyi, Katalin; Powell, Dwight A

    2015-06-01

    Diagnosis of latent tuberculosis infection is a problem in children because of lack of a diagnostic standard and potential impact of previous Bacille Calmette-Guérin vaccination and exposure to environmental mycobacteria. Effectiveness and usefulness of interferon-gamma release assays in infants and younger children have yet to be clearly demonstrated. Prospective cohort study including 109 children (4 months to 16 years) seen in an international adoption clinic at Nationwide Children's Hospital, Columbus, OH. Children were adopted from 14 countries, mostly (72.5%) from China, Russia and Ethiopia. Correspondence between tuberculin skin test (TST) and the T-SPOT.TB assay was evaluated. Factors associated with positive results on the TST and T-SPOT.TB were determined, and the impact of age on test performance was specifically addressed. TST was positive in 23.4% (25 of 107). T-SPOT.TB was positive in 4.6% (5 of 109). Overall agreement between TST and T-SPOT.TB was 71%, with prevalence-adjusted, bias-adjusted Kappa of 0.68. History of Mycobacterium tuberculosis exposure was associated with positive results on TST (odds ratio: 25.4, 95% confidence interval: 4.8-261.6, exact logistic regression) and T-SPOT.TB (odds ratio: 78.9, 95% confidence interval: 9.7-∞). All 5 children with positive T-SPOT.TB had TST induration ≥15 mm. No patient less than 1 year of age (n = 17) had positive TST or T-SPOT.TB. Positive TST was not associated with Bacille Calmette-Guérin vaccination or scar. TST was positive in a significant percentage of international adoptees. T-SPOT.TB was rarely positive and discordant results reflected negative T-SPOT.TB with positive TST. In this population latent tuberculosis infection may be over-estimated by TST. Regardless, in our context at the time of the study, treatment decisions were based upon TST results, not results of the T-SPOT.TB assay. Age was consistently associated with findings on TST and T-SPOT.TB with no positive result on either

  3. A systematic review of safety data reporting in clinical trials of vaccines against malaria, tuberculosis, and human immunodeficiency virus.

    PubMed

    Tamminga, Cindy; Kavanaugh, Michael; Fedders, Charlotte; Maiolatesi, Santina; Abraham, Neethu; Bonhoeffer, Jan; Heininger, Ulrich; Vasquez, Carlos S; Moorthy, Vasee S; Epstein, Judith E; Richie, Thomas L

    2013-08-02

    Malaria, tuberculosis (TB) and human immunodeficiency virus (HIV) are diseases with devastating effects on global public health, especially in the developing world. Clinical trials of candidate vaccines for these diseases are being conducted at an accelerating rate, and require accurate and consistent methods for safety data collection and reporting. We performed a systematic review of publications describing the safety results from clinical trials of malaria, TB and HIV vaccines, to ascertain the nature and consistency of safety data collection and reporting. The target for the review was pre-licensure trials for malaria, TB and HIV vaccines published in English from 2000 to 2009. Search strategies were customized for each of the databases utilized (MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews and the Database of Reviews and Effects). Data extracted included age of trial participants, vaccine platform, route and method of vaccine administration, duration of participant follow-up, reporting of laboratory abnormalities, and the type, case definitions, severity, reporting methods and internal reporting consistency of adverse events. Of 2278 publications screened, 124 were eligible for inclusion (malaria: 66, TB: 9, HIV: 49). Safety data reporting was found to be highly variable among publications and often incomplete: overall, 269 overlapping terms were used to describe specific adverse events. 17% of publications did not mention fever. Descriptions of severity or degree of relatedness to immunization of adverse events were frequently omitted. 26% (32/124) of publications failed to report data on serious adverse events. The review demonstrated lack of standardized safety data reporting in trials for vaccines against malaria, TB and HIV. Standardization of safety data collection and reporting should be encouraged to improve data quality and comparability. The search strategy missed studies published in languages other than English and excluded studies

  4. Protein Energy Malnutrition during Vaccination Has Limited Influence on Vaccine Efficacy but Abolishes Immunity if Administered during Mycobacterium tuberculosis Infection

    PubMed Central

    Hoang, Truc; Agger, Else Marie; Cassidy, Joseph P.; Christensen, Jan P.

    2015-01-01

    Protein energy malnutrition (PEM) increases susceptibility to infectious diseases, including tuberculosis (TB), but it is not clear how PEM influences vaccine-promoted immunity to TB. We demonstrate that PEM during low-level steady-state TB infection in a mouse model results in rapid relapse of Mycobacterium tuberculosis, as well as increased pathology, in both Mycobacterium bovis BCG-vaccinated and unvaccinated animals. PEM did not change the overall numbers of CD4 T cells in BCG-vaccinated animals but resulted in an almost complete loss of antigen-specific cytokine production. Furthermore, there was a change in cytokine expression characterized by a gradual loss of multifunctional antigen-specific CD4 T cells and an increased proportion of effector cells expressing gamma interferon and tumor necrosis factor alpha (IFN-γ+ TNF-α+ and IFN-γ+ cells). PEM during M. tuberculosis infection completely blocked the protection afforded by the H56-CAF01 subunit vaccine, and this was associated with a very substantial loss of the interleukin-2-positive memory CD4 T cells promoted by this vaccine. Similarly, PEM during the vaccination phase markedly reduced the H56-CAF01 vaccine response, influencing all cytokine-producing CD4 T cell subsets, with the exception of CD4 T cells positive for TNF-α only. Importantly, this impairment was reversible and resupplementation of protein during infection rescued both the vaccine-promoted T cell response and the protective effect of the vaccine against M. tuberculosis infection. PMID:25754202

  5. Ricin vaccine development.

    PubMed

    Smallshaw, Joan E; Vitetta, Ellen S

    2012-01-01

    In this chapter we discuss vaccines to protect against the highly toxic plant-derived toxin, ricin. Due to its prevalence, ease of use, and stability it has been used in sporadic incidents of espionage. There is also concern that it will be used as an agent of bioterrorism. As a result there has been a great deal of interest in developing a safe vaccine or antidote to protect humans, and in particular soldiers and first responders. Although multiple types of vaccines have been tested, at this time two recombinant vaccines are the leading candidates for the national vaccine stockpile. In terms of passive post-exposure protection, monoclonal neutralizing antibodies that passively protect animals are also under development. These vaccines and antibodies are discussed in the context of the toxicity and structure of ricin.

  6. Clinical development of Ebola vaccines

    PubMed Central

    Sridhar, Saranya

    2015-01-01

    The ongoing outbreak of Ebola virus disease in West Africa highlighted the lack of a licensed drug or vaccine to combat the disease and has renewed the urgency to develop a pipeline of Ebola vaccines. A number of different vaccine platforms are being developed by assessing preclinical efficacy in animal models and expediting clinical development. Over 15 different vaccines are in preclinical development and 8 vaccines are now in different stages of clinical evaluation. These vaccines include DNA vaccines, virus-like particles and viral vectors such as live replicating vesicular stomatitis virus (rVSV), human and chimpanzee adenovirus, and vaccinia virus. Recently, in preliminary results reported from the first phase III trial of an Ebola vaccine, the rVSV-vectored vaccine showed promising efficacy. This review charts this rapidly advancing area of research focusing on vaccines in clinical development and discusses the future opportunities and challenges faced in the licensure and deployment of Ebola vaccines. PMID:26668751

  7. Digital health for the End TB Strategy: developing priority products and making them work.

    PubMed

    Falzon, Dennis; Timimi, Hazim; Kurosinski, Pascal; Migliori, Giovanni Battista; Van Gemert, Wayne; Denkinger, Claudia; Isaacs, Chris; Story, Alistair; Garfein, Richard S; do Valle Bastos, Luis Gustavo; Yassin, Mohammed A; Rusovich, Valiantsin; Skrahina, Alena; Van Hoi, Le; Broger, Tobias; Abubakar, Ibrahim; Hayward, Andrew; Thomas, Bruce V; Temesgen, Zelalem; Quraishi, Subhi; von Delft, Dalene; Jaramillo, Ernesto; Weyer, Karin; Raviglione, Mario C

    2016-07-01

    In 2014, the World Health Organization (WHO) developed the End TB Strategy in response to a World Health Assembly Resolution requesting Member States to end the worldwide epidemic of tuberculosis (TB) by 2035. For the strategy's objectives to be realised, the next 20 years will need novel solutions to address the challenges posed by TB to health professionals, and to affected people and communities. Information and communication technology presents opportunities for innovative approaches to support TB efforts in patient care, surveillance, programme management and electronic learning. The effective application of digital health products at a large scale and their continued development need the engagement of TB patients and their caregivers, innovators, funders, policy-makers, advocacy groups, and affected communities.In April 2015, WHO established its Global Task Force on Digital Health for TB to advocate and support the development of digital health innovations in global efforts to improve TB care and prevention. We outline the group's approach to stewarding this process in alignment with the three pillars of the End TB Strategy. The supplementary material of this article includes target product profiles, as developed by early 2016, defining nine priority digital health concepts and products that are strategically positioned to enhance TB action at the country level. The content of this work is ©the authors or their employers. Design and branding are ©ERS 2016.

  8. Prevention of tuberculosis in rhesus macaques by a cytomegalovirus-based vaccine.

    PubMed

    Hansen, Scott G; Zak, Daniel E; Xu, Guangwu; Ford, Julia C; Marshall, Emily E; Malouli, Daniel; Gilbride, Roxanne M; Hughes, Colette M; Ventura, Abigail B; Ainslie, Emily; Randall, Kurt T; Selseth, Andrea N; Rundstrom, Parker; Herlache, Lauren; Lewis, Matthew S; Park, Haesun; Planer, Shannon L; Turner, John M; Fischer, Miranda; Armstrong, Christina; Zweig, Robert C; Valvo, Joseph; Braun, Jackie M; Shankar, Smitha; Lu, Lenette; Sylwester, Andrew W; Legasse, Alfred W; Messerle, Martin; Jarvis, Michael A; Amon, Lynn M; Aderem, Alan; Alter, Galit; Laddy, Dominick J; Stone, Michele; Bonavia, Aurelio; Evans, Thomas G; Axthelm, Michael K; Früh, Klaus; Edlefsen, Paul T; Picker, Louis J

    2018-02-01

    Despite widespread use of the bacille Calmette-Guérin (BCG) vaccine, tuberculosis (TB) remains a leading cause of global mortality from a single infectious agent (Mycobacterium tuberculosis or Mtb). Here, over two independent Mtb challenge studies, we demonstrate that subcutaneous vaccination of rhesus macaques (RMs) with rhesus cytomegalovirus vectors encoding Mtb antigen inserts (hereafter referred to as RhCMV/TB)-which elicit and maintain highly effector-differentiated, circulating and tissue-resident Mtb-specific CD4 + and CD8 + memory T cell responses-can reduce the overall (pulmonary and extrapulmonary) extent of Mtb infection and disease by 68%, as compared to that in unvaccinated controls, after intrabronchial challenge with the Erdman strain of Mtb at ∼1 year after the first vaccination. Fourteen of 34 RhCMV/TB-vaccinated RMs (41%) across both studies showed no TB disease by computed tomography scans or at necropsy after challenge (as compared to 0 of 17 unvaccinated controls), and ten of these RMs were Mtb-culture-negative for all tissues, an exceptional long-term vaccine effect in the RM challenge model with the Erdman strain of Mtb. These results suggest that complete vaccine-mediated immune control of highly pathogenic Mtb is possible if immune effector responses can intercept Mtb infection at its earliest stages.

  9. Early versus late BCG vaccination in HIV-1-exposed infants in Uganda: study protocol for a randomized controlled trial.

    PubMed

    Nankabirwa, Victoria; Tumwine, James K; Namugga, Olive; Tylleskär, Thorkild; Ndeezi, Grace; Robberstad, Bjarne; Netea, Mihai G; Sommerfelt, Halvor

    2017-03-31

    Bacillus Calmette-Guérin (BCG) vaccination may have nonspecific effects, i.e., effects on childhood morbidity and mortality that go beyond its effect on the risk of childhood tuberculosis (TB). Though the available scientific literature is mostly from observational studies, and is fraught with controversy, BCG vaccination at birth may protect infants in high-mortality populations against serious infections other than TB. Yet, other studies indicate that giving BCG later in infancy may modify immune responses to non-TB antigens and potentially enhance immunity, potentially also against tuberculosis (TB). It is unclear whether BCG vaccination very early in life offers adequate protection against TB and other infections among HIV-1-exposed children because even those who remain uninfected with HIV-1 show signs of impaired immunocompetence early in infancy. This study will compare BCG vaccination at birth with BCG vaccination at 14 weeks of age in HIV-1-exposed infants. This is an individually randomized controlled trial in 2200 HIV-1-exposed infants. The intervention is BCG vaccination within 24 h of birth while the comparator is BCG given at 14 weeks of age. The study co-primary outcomes are severe illness in the first 14 weeks of life, and production of tumor necrosis factor, interleukin (IL)-1β, IL-6 and interferon-γ in response to mycobacterial and nonmycobacterial antigens. The study is being conducted in three health centers in Uganda. A well-timed BCG vaccination could have important nonspecific effects in HIV-1-exposed infants. This trial could inform the development of appropriate timing of BCG vaccination for HIV-1-exposed infants. ClinicalTrials.gov, identifier: NCT02606526 . Registered on 12 November 2015.

  10. A New Recombinant BCG Vaccine Induces Specific Th17 and Th1 Effector Cells with Higher Protective Efficacy against Tuberculosis

    PubMed Central

    da Costa, Adeliane Castro; Costa-Júnior, Abadio de Oliveira; de Oliveira, Fábio Muniz; Nogueira, Sarah Veloso; Rosa, Joseane Damaceno; Resende, Danilo Pires; Kipnis, André; Junqueira-Kipnis, Ana Paula

    2014-01-01

    Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that is a major public health problem. The vaccine used for TB prevention is Mycobacterium bovis bacillus Calmette-Guérin (BCG), which provides variable efficacy in protecting against pulmonary TB among adults. Consequently, several groups have pursued the development of a new vaccine with a superior protective capacity to that of BCG. Here we constructed a new recombinant BCG (rBCG) vaccine expressing a fusion protein (CMX) composed of immune dominant epitopes from Ag85C, MPT51, and HspX and evaluated its immunogenicity and protection in a murine model of infection. The stability of the vaccine in vivo was maintained for up to 20 days post-vaccination. rBCG-CMX was efficiently phagocytized by peritoneal macrophages and induced nitric oxide (NO) production. Following mouse immunization, this vaccine induced a specific immune response in cells from lungs and spleen to the fusion protein and to each of the component recombinant proteins by themselves. Vaccinated mice presented higher amounts of Th1, Th17, and polyfunctional specific T cells. rBCG-CMX vaccination reduced the extension of lung lesions caused by challenge with Mtb as well as the lung bacterial load. In addition, when this vaccine was used in a prime-boost strategy together with rCMX, the lung bacterial load was lower than the result observed by BCG vaccination. This study describes the creation of a new promising vaccine for TB that we hope will be used in further studies to address its safety before proceeding to clinical trials. PMID:25398087

  11. 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

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

    PubMed

    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

    2016-02-01

    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.

  13. Engineering new mycobacterial vaccine design for HIV–TB pediatric vaccine vectored by lysine auxotroph of BCG

    PubMed Central

    Saubi, Narcís; Gea-Mallorquí, Ester; Ferrer, Pau; Hurtado, Carmen; Sánchez-Úbeda, Sara; Eto, Yoshiki; Gatell, Josep M; Hanke, Tomáš; Joseph, Joan

    2014-01-01

    In this study, we have engineered a new mycobacterial vaccine design by using an antibiotic-free plasmid selection system. We assembled a novel Escherichia coli (E. coli)–mycobacterial shuttle plasmid p2auxo.HIVA, expressing the HIV-1 clade A immunogen HIVA. This shuttle vector employs an antibiotic resistance-free mechanism for plasmid selection and maintenance based on glycine complementation in E. coli and lysine complementation in mycobacteria. This plasmid was first transformed into glycine auxotroph of E. coli strain and subsequently transformed into lysine auxotroph of Mycobacterium bovis BCG strain to generate vaccine BCG.HIVA2auxo. We demonstrated that the episomal plasmid p2auxo.HIVA was stable in vivo over a 7-week period and genetically and phenotypically characterized the BCG.HIVA2auxo vaccine strain. The BCG.HIVA2auxo vaccine in combination with modified vaccinia virus Ankara (MVA). HIVA was safe and induced HIV-1 and Mycobacterium tuberculosis-specific interferon-γ-producing T-cell responses in adult BALB/c mice. Polyfunctional HIV-1-specific CD8+ T cells, which produce interferon-γ and tumor necrosis factor-α and express the degranulation marker CD107a, were induced. Thus, we engineered a novel, safer, good laboratory practice–compatible BCG-vectored vaccine using prototype immunogen HIVA. This antibiotic-free plasmid selection system based on “double” auxotrophic complementation might be a new mycobacterial vaccine platform to develop not only recombinant BCG-based vaccines expressing second generation of HIV-1 immunogens but also other major pediatric pathogens to prime protective response soon after birth. PMID:26015961

  14. Impact of piglet oral vaccination against tuberculosis in endemic free-ranging wild boar populations.

    PubMed

    Díez-Delgado, Iratxe; Sevilla, Iker A; Romero, Beatriz; Tanner, Eleanor; Barasona, Jose A; White, Andrew R; Lurz, Peter W W; Boots, Mike; de la Fuente, José; Dominguez, Lucas; Vicente, Joaquin; Garrido, Joseba M; Juste, Ramón A; Aranaz, Alicia; Gortazar, Christian

    2018-07-01

    The Eurasian wild boar (Sus scrofa) is the main wild reservoir of the Mycobacterium tuberculosis complex in Mediterranean woodlands and a key risk factor for cattle tuberculosis (TB) breakdowns. Wild boar vaccination therefore has the potential to be a valuable tool for TB control. We tested two orally delivered vaccines, heat-inactivated Mycobacterium bovis (IV) and BCG, in four sites (two per vaccine type: one Managed and one Natural or unmanaged) during four years. TB was also monitored in 15 unvaccinated sites (spatial control), as well as in all sites from one year prior to intervention (temporal control). The rationale is that by vaccinating 2-6 month old wild boar piglets we can reduce disease at the population level during the study period. This is achievable due to the fast turnover of wild boar populations. Vaccine baits were deployed using selective piglet feeders and this method proved highly successful with uptake rates of 50 to 74% in Natural sites and 89 to 92% in Managed sites. This is relevant for the potential delivery of vaccines to control other diseases, too. Local wild boar TB prevalence at the beginning of the study was already high ranging from 50 to 100%. TB prevalence increased in unvaccinated sites (6%), while a significant decline occurred in the Managed IV site (34%). Changes recorded in the remaining sites were not significant. The short-term impact of vaccination observed in the field was complemented by mathematical modelling, representative of the field system, which examined the long-term impact and showed that vaccination of piglets reduced prevalence and increased abundance at the population level. We conclude that IV could become part of integrated TB control schemes, although its application must be tailored for each specific site. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes

    PubMed Central

    Rosada, Rogério S; Torre, Lucimara Gaziola de la; Frantz, Fabiani G; Trombone, Ana PF; Zárate-Bladés, Carlos R; Fonseca, Denise M; Souza, Patrícia RM; Brandão, Izaíra T; Masson, Ana P; Soares, Édson G; Ramos, Simone G; Faccioli, Lúcia H; Silva, Célio L; Santana, Maria HA; Coelho-Castelo, Arlete AM

    2008-01-01

    Background The greatest challenges in vaccine development include optimization of DNA vaccines for use in humans, creation of effective single-dose vaccines, development of delivery systems that do not involve live viruses, and the identification of effective new adjuvants. Herein, we describe a novel, simple technique for efficiently vaccinating mice against tuberculosis (TB). Our technique consists of a single-dose, genetic vaccine formulation of DNA-hsp65 complexed with cationic liposomes and administered intranasally. Results We developed a novel and non-toxic formulation of cationic liposomes, in which the DNA-hsp65 vaccine was entrapped (ENTR-hsp65) or complexed (COMP-hsp65), and used to immunize mice by intramuscular or intranasal routes. Although both liposome formulations induced a typical Th1 pattern of immune response, the intramuscular route of delivery did not reduce the number of bacilli. However, a single intranasal immunization with COMP-hsp65, carrying as few as 25 μg of plasmid DNA, leads to a remarkable reduction of the amount of bacilli in lungs. These effects were accompanied by increasing levels of IFN-γ and lung parenchyma preservation, results similar to those found in mice vaccinated intramuscularly four times with naked DNA-hsp65 (total of 400 μg). Conclusion Our objective was to overcome the significant obstacles currently facing DNA vaccine development. Our results in the mouse TB model showed that a single intranasal dose of COMP-hsp65 elicited a cellular immune response that was as strong as that induced by four intramuscular doses of naked-DNA. This formulation allowed a 16-fold reduction in the amount of DNA administered. Moreover, we demonstrated that this vaccine is safe, biocompatible, stable, and easily manufactured at a low cost. We believe that this strategy can be applied to human vaccines to TB in a single dose or in prime-boost protocols, leading to a tremendous impact on the control of this infectious disease. PMID

  16. Vaccine development for syphilis.

    PubMed

    Lithgow, Karen V; Cameron, Caroline E

    2017-01-01

    Syphilis, caused by the spirochete Treponema pallidum subspecies pallidum, continues to be a globally prevalent disease despite remaining susceptible to penicillin treatment. Syphilis vaccine development is a viable preventative approach that will serve to complement public health-oriented syphilis prevention, screening and treatment initiatives to deliver a two-pronged approach to stemming disease spread worldwide. Areas covered: This article provides an overview of the need for development of a syphilis vaccine, summarizes significant information that has been garnered from prior syphilis vaccine studies, discusses the critical aspects of infection that would have to be targeted by a syphilis vaccine, and presents the current understanding within the field of the correlates of protection needed to be achieved through vaccination. Expert commentary: Syphilis vaccine development should be considered a priority by industry, regulatory and funding agencies, and should be appropriately promoted and supported.

  17. Sustainable vaccine development: a vaccine manufacturer's perspective.

    PubMed

    Rappuoli, Rino; Hanon, Emmanuel

    2018-05-08

    Vaccination remains the most cost-effective public health intervention after clean water, and the benefits impressively outweigh the costs. The efforts needed to fulfill the steadily growing demands for next-generation and novel vaccines designed for emerging pathogens and new indications are only realizable in a sustainable business model. Vaccine development can be fast-tracked through strengthening international collaborations, and the continuous innovation of technologies to accelerate their design, development, and manufacturing. However, these processes should be supported by a balanced project portfolio, and by managing sustainable vaccine procurement strategies for different types of markets. Collectively this will allow a gradual shift to a more streamlined and profitable vaccine production, which can significantly contribute to the worldwide effort to shape global health. Copyright © 2018 GlaxoSmithKine Biologicals SA. Published by Elsevier Ltd.. All rights reserved.

  18. Analysis of Host Responses to Mycobacterium tuberculosis Antigens in a Multi-Site Study of Subjects with Different TB and HIV Infection States in Sub-Saharan Africa

    PubMed Central

    Sutherland, Jayne S.; Lalor, Maeve K.; Black, Gillian F.; Ambrose, Lyn R.; Loxton, Andre G.; Chegou, Novel N.; Kassa, Desta; Mihret, Adane; Howe, Rawleigh; Mayanja-Kizza, Harriet; Gomez, Marie P.; Donkor, Simon; Franken, Kees; Hanekom, Willem; Klein, Michel R.; Parida, Shreemanta K.; Boom, W. Henry; Thiel, Bonnie A.; Crampin, Amelia C.; Ota, Martin; Walzl, Gerhard; Ottenhoff, Tom H. M.; Dockrell, Hazel M.; Kaufmann, Stefan H. E.

    2013-01-01

    Background Tuberculosis (TB) remains a global health threat with 9 million new cases and 1.4 million deaths per year. In order to develop a protective vaccine, we need to define the antigens expressed by Mycobacterium tuberculosis (Mtb), which are relevant to protective immunity in high-endemic areas. Methods We analysed responses to 23 Mtb antigens in a total of 1247 subjects with different HIV and TB status across 5 geographically diverse sites in Africa (South Africa, The Gambia, Ethiopia, Malawi and Uganda). We used a 7-day whole blood assay followed by IFN-γ ELISA on the supernatants. Antigens included PPD, ESAT-6 and Ag85B (dominant antigens) together with novel resuscitation-promoting factors (rpf), reactivation proteins, latency (Mtb DosR regulon-encoded) antigens, starvation-induced antigens and secreted antigens. Results There was variation between sites in responses to the antigens, presumably due to underlying genetic and environmental differences. When results from all sites were combined, HIV- subjects with active TB showed significantly lower responses compared to both TST- and TST+ contacts to latency antigens (Rv0569, Rv1733, Rv1735, Rv1737) and the rpf Rv0867; whilst responses to ESAT-6/CFP-10 fusion protein (EC), PPD, Rv2029, TB10.3, and TB10.4 were significantly higher in TST+ contacts (LTBI) compared to TB and TST- contacts fewer differences were seen in subjects with HIV co-infection, with responses to the mitogen PHA significantly lower in subjects with active TB compared to those with LTBI and no difference with any antigen. Conclusions Our multi-site study design for testing novel Mtb antigens revealed promising antigens for future vaccine development. The IFN-γ ELISA is a cheap and useful tool for screening potential antigenicity in subjects with different ethnic backgrounds and across a spectrum of TB and HIV infection states. Analysis of cytokines other than IFN-γ is currently on-going to determine correlates of protection, which may

  19. Analysis of host responses to Mycobacterium tuberculosis antigens in a multi-site study of subjects with different TB and HIV infection states in sub-Saharan Africa.

    PubMed

    Sutherland, Jayne S; Lalor, Maeve K; Black, Gillian F; Ambrose, Lyn R; Loxton, Andre G; Chegou, Novel N; Kassa, Desta; Mihret, Adane; Howe, Rawleigh; Mayanja-Kizza, Harriet; Gomez, Marie P; Donkor, Simon; Franken, Kees; Hanekom, Willem; Klein, Michel R; Parida, Shreemanta K; Boom, W Henry; Thiel, Bonnie A; Crampin, Amelia C; Ota, Martin; Walzl, Gerhard; Ottenhoff, Tom H M; Dockrell, Hazel M; Kaufmann, Stefan H E

    2013-01-01

    Tuberculosis (TB) remains a global health threat with 9 million new cases and 1.4 million deaths per year. In order to develop a protective vaccine, we need to define the antigens expressed by Mycobacterium tuberculosis (Mtb), which are relevant to protective immunity in high-endemic areas. We analysed responses to 23 Mtb antigens in a total of 1247 subjects with different HIV and TB status across 5 geographically diverse sites in Africa (South Africa, The Gambia, Ethiopia, Malawi and Uganda). We used a 7-day whole blood assay followed by IFN-γ ELISA on the supernatants. Antigens included PPD, ESAT-6 and Ag85B (dominant antigens) together with novel resuscitation-promoting factors (rpf), reactivation proteins, latency (Mtb DosR regulon-encoded) antigens, starvation-induced antigens and secreted antigens. There was variation between sites in responses to the antigens, presumably due to underlying genetic and environmental differences. When results from all sites were combined, HIV- subjects with active TB showed significantly lower responses compared to both TST(-) and TST(+) contacts to latency antigens (Rv0569, Rv1733, Rv1735, Rv1737) and the rpf Rv0867; whilst responses to ESAT-6/CFP-10 fusion protein (EC), PPD, Rv2029, TB10.3, and TB10.4 were significantly higher in TST(+) contacts (LTBI) compared to TB and TST(-) contacts fewer differences were seen in subjects with HIV co-infection, with responses to the mitogen PHA significantly lower in subjects with active TB compared to those with LTBI and no difference with any antigen. Our multi-site study design for testing novel Mtb antigens revealed promising antigens for future vaccine development. The IFN-γ ELISA is a cheap and useful tool for screening potential antigenicity in subjects with different ethnic backgrounds and across a spectrum of TB and HIV infection states. Analysis of cytokines other than IFN-γ is currently on-going to determine correlates of protection, which may be useful for vaccine efficacy

  20. Gene mutations in Mycobacterium tuberculosis: multidrug-resistant TB as an emerging global public health crisis.

    PubMed

    Mishra, Rahul; Shukla, Priyanka; Huang, Wei; Hu, Ning

    2015-01-01

    Against a constant background of established infections, epidemics of new and old infectious diseases periodically emerge, greatly magnifying the global burden of infections. TB poses formidable challenges to the global health at the public health and scientific level by acquiring gene mutation into anti TB drugs specially rifampin and isoniazid which leads resistant to drug regime and treatment forms. Our tools to combat MDR (multidrug resistant) TB are dangerously out of date and ineffective. Besides new tools (TB drugs, vaccines, diagnostics), we also need new strategies to identify key Mycobacterium tuberculosis and human host interaction. It is all equally important that we build up high quality clinical trial capacity and bio banks for TB biomarkers identification. But most important is global commitment at all levels to roll back TB before it expose us again. Rapid development of drug resistance caused by M. tuberculosis has lead to measure resistance accurately and easily. This knowledge will certainly help us to understand how to prevent the occurrence of drug resistance as well as identifying genes associated with new drug resistance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Differential cellular recognition pattern to M. tuberculosis targets defined by IFN-γ and IL-17 production in blood from TB + patients from Honduras as compared to health care workers: TB and immune responses in patients from Honduras.

    PubMed

    Alvarez-Corrales, Nancy; Ahmed, Raija K; Rodriguez, Carol A; Balaji, Kithiganahalli N; Rivera, Rebeca; Sompallae, Ramakrishna; Vudattu, Nalini K; Hoffner, Sven E; Zumla, Alimuddin; Pineda-Garcia, Lelany; Maeurer, Markus

    2013-03-06

    A better understanding of the quality of cellular immune responses directed against molecularly defined targets will guide the development of TB diagnostics and identification of molecularly defined, clinically relevant M.tb vaccine candidates. Recombinant proteins (n = 8) and peptide pools (n = 14) from M. tuberculosis (M.tb) targets were used to compare cellular immune responses defined by IFN-γ and IL-17 production using a Whole Blood Assay (WBA) in a cohort of 148 individuals, i.e. patients with TB + (n = 38), TB- individuals with other pulmonary diseases (n = 81) and individuals exposed to TB without evidence of clinical TB (health care workers, n = 29). M.tb antigens Rv2958c (glycosyltransferase), Rv2962c (mycolyltransferase), Rv1886c (Ag85B), Rv3804c (Ag85A), and the PPE family member Rv3347c were frequently recognized, defined by IFN-γ production, in blood from healthy individuals exposed to M.tb (health care workers). A different recognition pattern was found for IL-17 production in blood from M.tb exposed individuals responding to TB10.4 (Rv0288), Ag85B (Rv1886c) and the PPE family members Rv0978c and Rv1917c. The pattern of immune target recognition is different in regard to IFN-γ and IL-17 production to defined molecular M.tb targets in PBMCs from individuals frequently exposed to M.tb. The data represent the first mapping of cellular immune responses against M.tb targets in TB patients from Honduras.

  2. Vaccine development for syphilis

    PubMed Central

    Lithgow, Karen V.

    2017-01-01

    Introduction Syphilis, caused by the spirochete Treponema pallidum subspecies pallidum, continues to be a globally prevalent disease despite remaining susceptible to penicillin treatment. Syphilis vaccine development is a viable preventative approach that will serve to complement public health-oriented syphilis prevention, screening and treatment initiatives to deliver a two-pronged approach to stemming disease spread worldwide. Areas covered This article provides an overview of the need for development of a syphilis vaccine, summarizes significant information that has been garnered from prior syphilis vaccine studies, discusses the critical aspects of infection that would have to be targeted by a syphilis vaccine, and presents the current understanding within the field of the correlates of protection needed to be achieved through vaccination. Expert commentary Syphilis vaccine development should be considered a priority by industry, regulatory and funding agencies, and should be appropriately promoted and supported. PMID:27328030

  3. Exposure to human alveolar lining fluid enhances Mycobacterium bovis BCG vaccine efficacy against Mycobacterium tuberculosis infection in a CD8+ T-cell-dependent manner.

    PubMed

    Moliva, J I; Hossfeld, A P; Canan, C H; Dwivedi, V; Wewers, M D; Beamer, G; Turner, J; Torrelles, J B

    2018-05-01

    Current tuberculosis (TB) treatments include chemotherapy and preventative vaccination with Mycobacterium bovis Bacillus Calmette-Guérin (BCG). In humans, however, BCG vaccination fails to fully protect against pulmonary TB. Few studies have considered the impact of the human lung mucosa (alveolar lining fluid (ALF)), which modifies the Mycobacterium tuberculosis (M.tb) cell wall, revealing alternate antigenic epitopes on the bacterium surface that alter its pathogenicity. We hypothesized that ALF-induced modification of BCG would induce better protection against aerosol infection with M.tb. Here we vaccinated mice with ALF-exposed BCG, mimicking the mycobacterial cell surface properties that would be present in the lung during M.tb infection. ALF-exposed BCG-vaccinated mice were more effective at reducing M.tb bacterial burden in the lung and spleen, and had reduced lung inflammation at late stages of M.tb infection. Improved BCG efficacy was associated with increased numbers of memory CD8 + T cells, and CD8 + T cells with the potential to produce interferon-γ in the lung in response to M.tb challenge. Depletion studies confirmed an essential role for CD8 + T cells in controlling M.tb bacterial burden. We conclude that ALF modifications to the M.tb cell wall in vivo are relevant in the context of vaccine design.

  4. The Recombinant Bacille Calmette-Guérin Vaccine VPM1002: Ready for Clinical Efficacy Testing.

    PubMed

    Nieuwenhuizen, Natalie E; Kulkarni, Prasad S; Shaligram, Umesh; Cotton, Mark F; Rentsch, Cyrill A; Eisele, Bernd; Grode, Leander; Kaufmann, Stefan H E

    2017-01-01

    The only licensed vaccine against tuberculosis (TB), bacille Calmette-Guérin (BCG), protects against severe extrapulmonary forms of TB but is virtually ineffective against the most prevalent form of the disease, pulmonary TB. BCG was genetically modified at the Max Planck Institute for Infection Biology to improve its immunogenicity by replacing the urease C encoding gene with the listeriolysin encoding gene from Listeria monocytogenes . Listeriolysin perturbates the phagosomal membrane at acidic pH. Urease C is involved in neutralization of the phagosome harboring BCG. Its depletion allows for rapid phagosome acidification and promotes phagolysosome fusion. As a result, BCGΔ ureC :: hly (VPM1002) promotes apoptosis and autophagy and facilitates release of mycobacterial antigens into the cytosol. In preclinical studies, VPM1002 has been far more efficacious and safer than BCG. The vaccine was licensed to Vakzine Projekt Management and later sublicensed to the Serum Institute of India Pvt. Ltd., the largest vaccine producer in the world. The vaccine has passed phase I clinical trials in Germany and South Africa, demonstrating its safety and immunogenicity in young adults. It was also successfully tested in a phase IIa randomized clinical trial in healthy South African newborns and is currently undergoing a phase IIb study in HIV exposed and unexposed newborns. A phase II/III clinical trial will commence in India in 2017 to assess efficacy against recurrence of TB. The target indications for VPM1002 are newborn immunization to prevent TB as well as post-exposure immunization in adults to prevent TB recurrence. In addition, a Phase I trial in non-muscle invasive bladder cancer patients has been completed, and phase II trials are ongoing. This review describes the development of VPM1002 from the drawing board to its clinical assessment.

  5. Tuberculosis vaccine development: recent progress.

    PubMed

    Orme, I M; McMurray, D N; Belisle, J T

    2001-03-01

    Recent years have seen a renewed effort to develop new vaccines against tuberculosis. As a result, several promising avenues of research have developed, including the production of recombinant vaccines, auxotrophic vaccines, DNA vaccines and subunit vaccines. In this article we briefly review this work, as well as consider the pros and cons of the animal models needed to test these new vaccines. Screening to date has been carried out in mouse and guinea pig models, which have been used to obtain basic information such as the effect of the vaccine on bacterial load, and whether the vaccine can prevent or reduce lung pathology. The results to date lead us to be optimistic that new candidate vaccines could soon be considered for evaluation in clinical trials.

  6. Pros and cons of BCG vaccination in countries with low incidence of tuberculosis.

    PubMed

    Tala, E O; Tala-Heikkilä, M M

    1994-07-01

    Preventive bacille Calmette-Guérin (BCG) vaccination, together with case finding and effective chemotherapy, has formed an integral part of the tuberculosis (TB) control program in most countries. In some low-incidence countries the balance of prevention has been more on the side of chemoprophylaxis than of BCG vaccination. The time clearly has come when the strategy of mass BCG vaccination no longer is indicated medically, nor is it cost-effective. The pros and cons of the programs need to be critically evaluated against the present epidemiological background, taking into account the facts that TB, the killer disease, is recovering strength, human immunodeficiency virus infection is on the increase, and multidrug-resistant TB has changed the outcome of this previously fully curable disease. Although no longer appropriate for mass programs, BCG vaccination still should be considered for the protection of selected risk groups in low-incidence countries. The overall efficacy may be of the order 50% to 80%, but the variation is great. Therefore, further research urgently is needed on the effectiveness of BCG as an intervention in local TB programs.

  7. Rhodococcus equi (Prescottella equi) vaccines; the future of vaccine development.

    PubMed

    Giles, C; Vanniasinkam, T; Ndi, S; Barton, M D

    2015-09-01

    For decades researchers have been targeting prevention of Rhodococcus equi (Rhodococcus hoagui/Prescottella equi) by vaccination and the horse breeding industry has supported the ongoing efforts by researchers to develop a safe and cost effective vaccine to prevent disease in foals. Traditional vaccines including live, killed and attenuated (physical and chemical) vaccines have proved to be ineffective and more modern molecular-based vaccines including the DNA plasmid, genetically attenuated and subunit vaccines have provided inadequate protection of foals. Newer, bacterial vector vaccines have recently shown promise for R. equi in the mouse model. This article describes the findings of key research in R. equi vaccine development and looks at alternative methods that may potentially be utilised. © 2014 EVJ Ltd.

  8. Intranasal mucosal boosting with an adenovirus-vectored vaccine markedly enhances the protection of BCG-primed guinea pigs against pulmonary tuberculosis.

    PubMed

    Xing, Zhou; McFarland, Christine T; Sallenave, Jean-Michel; Izzo, Angelo; Wang, Jun; McMurray, David N

    2009-06-10

    Recombinant adenovirus-vectored (Ad) tuberculosis (TB) vaccine platform has demonstrated great potential to be used either as a stand-alone or a boost vaccine in murine models. However, Ad TB vaccine remains to be evaluated in a more relevant and sensitive guinea pig model of pulmonary TB. Many vaccine candidates shown to be effective in murine models have subsequently failed to pass the test in guinea pig models. Specific pathogen-free guinea pigs were immunized with BCG, AdAg85A intranasally (i.n), AdAg85A intramuscularly (i.m), BCG boosted with AdAg85A i.n, BCG boosted with AdAg85A i.m, or treated only with saline. The animals were then infected by a low-dose aerosol of M. tuberculosis (M.tb). At the specified times, the animals were sacrificed and the levels of infection in the lung and spleen were assessed. In separate studies, the long-term disease outcome of infected animals was monitored until the termination of this study. Immunization with Ad vaccine alone had minimal beneficial effects. Immunization with BCG alone and BCG prime-Ad vaccine boost regimens significantly reduced the level of M.tb infection in the tissues to a similar extent. However, while BCG alone prolonged the survival of infected guinea pigs, the majority of BCG-immunized animals succumbed by 53 weeks post-M.tb challenge. In contrast, intranasal or intramuscular Ad vaccine boosting of BCG-primed animals markedly improved the survival rate with 60% of BCG/Ad i.n- and 40% of BCG/Ad i.m-immunized guinea pigs still surviving by 74 weeks post-aerosol challenge. Boosting, particularly via the intranasal mucosal route, with AdAg85A vaccine is able to significantly enhance the long-term survival of BCG-primed guinea pigs following pulmonary M.tb challenge. Our results thus support further evaluation of this viral-vectored TB vaccine in clinical trials.

  9. Balancing Trained Immunity with Persistent Immune Activation and the Risk of Simian Immunodeficiency Virus Infection in Infant Macaques Vaccinated with Attenuated Mycobacterium tuberculosis or Mycobacterium bovis BCG Vaccine

    PubMed Central

    Jensen, Kara; dela Pena-Ponce, Myra Grace; Piatak, Michael; Shoemaker, Rebecca; Oswald, Kelli; Jacobs, William R.; Fennelly, Glenn; Lucero, Carissa; Mollan, Katie R.; Hudgens, Michael G.; Amedee, Angela; Kozlowski, Pamela A.; Estes, Jacob D.; Lifson, Jeffrey D.; Van Rompay, Koen K. A.; Larsen, Michelle

    2016-01-01

    ABSTRACT Our goal is to develop a pediatric combination vaccine to protect the vulnerable infant population against human immunodeficiency virus type 1 (HIV-1) and tuberculosis (TB) infections. The vaccine consists of an auxotroph Mycobacterium tuberculosis strain that coexpresses HIV antigens. Utilizing an infant rhesus macaque model, we have previously shown that this attenuated M. tuberculosis (AMtb)-simian immunodeficiency virus (SIV) vaccine is immunogenic, and although the vaccine did not prevent oral SIV infection, a subset of vaccinated animals was able to partially control virus replication. However, unexpectedly, vaccinated infants required fewer SIV exposures to become infected compared to naive controls. Considering that the current TB vaccine, Mycobacterium bovis bacillus Calmette-Guérin (BCG), can induce potent innate immune responses and confer pathogen-unspecific trained immunity, we hypothesized that an imbalance between enhanced myeloid cell function and immune activation might have influenced the outcome of oral SIV challenge in AMtb-SIV-vaccinated infants. To address this question, we used archived samples from unchallenged animals from our previous AMtb-SIV vaccine studies and vaccinated additional infant macaques with BCG or AMtb only. Our results show that vaccinated infants, regardless of vaccine strain or regimen, had enhanced myeloid cell responses. However, CD4+ T cells were concurrently activated, and the persistence of these activated target cells in oral and/or gastrointestinal tissues may have facilitated oral SIV infection. Immune activation was more pronounced in BCG-vaccinated infant macaques than in AMtb-vaccinated infant macaques, indicating a role for vaccine attenuation. These findings underline the importance of understanding the interplay of vaccine-induced immunity and immune activation and its effect on HIV acquisition risk and outcome in infants. PMID:27655885

  10. Chinese vaccine products go global: vaccine development and quality control.

    PubMed

    Xu, Miao; Liang, Zhenglun; Xu, Yinghua; Wang, Junzhi

    2015-05-01

    Through the continuous efforts of several generations, China has become one of the few countries in the world that is capable of independently addressing all the requirements by the Expanded Program on Immunization. Regulatory science is applied to continuously improve the vaccine regulatory system. Passing the prequalification by WHO has allowed Chinese vaccine products to go global. Chinese vaccine products not only secure disease prevention and control domestically but also serve the needs for international public health. This article describes the history of Chinese vaccine development, the current situation of Chinese vaccine industry and its contribution to the prevention and control of infectious diseases. We also share our experience of national quality control and vaccine regulation during the past decades. China's experience in vaccine development and quality control can benefit other countries and regions worldwide, including the developing countries.

  11. Hepcidin deficiency and iron deficiency do not alter tuberculosis susceptibility in a murine M.tb infection model

    PubMed Central

    Harrington-Kandt, Rachel; Stylianou, Elena; Eddowes, Lucy A.; Lim, Pei Jin; Stockdale, Lisa; Pinpathomrat, Nawamin; Bull, Naomi; Pasricha, Janet; Ulaszewska, Marta; Beglov, Yulia; Vaulont, Sophie

    2018-01-01

    Tuberculosis (TB), caused by the macrophage-tropic pathogen Mycobacterium tuberculosis (M.tb) is a highly prevalent infectious disease. Since an immune correlate of protection or effective vaccine have yet to be found, continued research into host-pathogen interactions is important. Previous literature reports links between host iron status and disease outcome for many infections, including TB. For some extracellular bacteria, the iron regulatory hormone hepcidin is essential for protection against infection. Here, we investigated hepcidin (encoded by Hamp1) in the context of murine M.tb infection. Female C57BL/6 mice were infected with M.tb Erdman via aerosol. Hepatic expression of iron-responsive genes was measured by qRT-PCR and bacterial burden determined in organ homogenates. We found that hepatic Hamp1 mRNA levels decreased post-infection, and correlated with a marker of BMP/SMAD signalling pathways. Next, we tested the effect of Hamp1 deletion, and low iron diets, on M.tb infection. Hamp1 knockout mice did not have a significantly altered M.tb mycobacterial load in either the lungs or spleen. Up to 10 weeks of dietary iron restriction did not robustly affect disease outcome despite causing iron deficiency anaemia. Taken together, our data indicate that unlike with many other infections, hepcidin is decreased following M.tb infection, and show that hepcidin ablation does not influence M.tb growth in vivo. Furthermore, because even severe iron deficiency did not affect M.tb mycobacterial load, we suggest that the mechanisms M.tb uses to scavenge iron from the host must be extremely efficient, and may therefore represent potential targets for drugs and vaccines. PMID:29324800

  12. Policy making for vaccine use as a driver of vaccine innovation and development in the developed world.

    PubMed

    Seib, Katherine; Pollard, Andrew J; de Wals, Philippe; Andrews, Ross M; Zhou, Fangjun; Hatchett, Richard J; Pickering, Larry K; Orenstein, Walter A

    2017-03-07

    In the past 200years, vaccines have had unmistakable impacts on public health including declines in morbidity and mortality, most markedly in economically-developed countries. Highly engineered vaccines including vaccines for conditions other than infectious diseases are expected to dominate future vaccine development. We examine immunization vaccine policy as a driver of vaccine innovation and development. The pathways to recommendation for use of licensed vaccines in the US, UK, Canada and Australia have been similar, including: expert review of disease epidemiology, disease burden and severity; vaccine immunogenicity, efficacy and safety; programmatic feasibility; public demand; and increasingly cost-effectiveness. Other attributes particularly important in development of future vaccines are likely to include: duration of immunity for improved vaccines such as pertussis; a greater emphasis on optimizing community protection rather than direct protection only; programmatic implementation, feasibility, improvements (as in the case of development of a universal influenza vaccine); public concerns/confidence/fears related to outbreak pathogens like Ebola and Zika virus; and major societal burden for combating hard to treat diseases like HIV and antimicrobial resistant pathogens. Driving innovation and production of future vaccines faces enormous economic hurdles as available approaches, technologies and regulatory pathways become more complex. As such, cost-mitigating strategies and focused, aligned efforts (by governments, private organizations, and private-public partnerships) will likely be needed to continue to spur major advances in vaccine technologies and development. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Advances & challenges in leptospiral vaccine development.

    PubMed

    Bashiru, Garba; Bahaman, Abdul Rani

    2018-01-01

    Considerable progress has been made in the field of leptospiral vaccines development since its first use as a killed vaccine in guinea pigs. Despite the fact that the immunity conferred is restricted to serovars with closely related lipopolysaccharide antigen, certain vaccines have remained useful, especially in endemic regions, for the protection of high-risk individuals. Other conventional vaccines such as the live-attenuated vaccine and lipopolysaccharide (LPS) vaccine have not gained popularity due to the reactive response that follows their administration and the lack of understanding of the pathogenesis of leptospirosis. With the recent breakthrough and availability of complete genome sequences of Leptospira, development of novel vaccine including recombinant protein vaccine using reverse vaccinology approaches has yielded encouraging results. However, factors hindering the development of effective leptospiral vaccines include variation in serovar distribution from region to region, establishment of renal carrier status following vaccination and determination of the dose and endpoint titres acceptable as definitive indicators of protective immunity. In this review, advancements and progress made in LPS-based vaccines, killed- and live-attenuated vaccines, recombinant peptide vaccines and DNA vaccines against leptospirosis are highlighted.

  14. The global fight to develop antipoverty vaccines in the anti-vaccine era.

    PubMed

    Hotez, Peter J

    2018-02-02

    Antipoverty vaccines are the vaccines targeting a group of approximately 20 neglected tropical diseases (NTDs), as currently defined by the World Health Organization (WHO). The "antipoverty" moniker refers to the fact that NTDs trap populations in poverty due to their chronic and deleterious effects on child intellect and worker productivity. Therefore, NTD vaccines can be expected to promote both global health and economic advancement. Unfortunately, antipoverty vaccine development has lagged behind vaccines for major childhood infections and pandemic threats, despite evidence for their cost-effectiveness and cost-savings. Currently, the only licensed vaccines for NTDs include those for yellow fever, dengue, and rabies, although several other NTD vaccines for hookworm disease, schistosomiasis, leishmaniasis, and Zika and Ebola virus infections are in different stages of clinical development, while others are at the preclinical development stage. With the exception of the viral NTD vaccines there so far has been minimal industry interest in the antipoverty vaccines, leaving their development to a handful of non-profit product development partnerships. The major scientific and geopolitical hurdles to antipoverty vaccine development are discussed, including a rising antivaccine ("antivax") movement now entering highly populated low- and middle-income countries.

  15. Farmer attitudes to vaccination and culling of badgers in controlling bovine tuberculosis.

    PubMed

    Warren, M; Lobley, M; Winter, M

    2013-07-13

    Controversy persists in England, Wales and Northern Ireland concerning methods of controlling the transmission of bovine tuberculosis (bTB) between badgers and cattle. The National Trust, a major land-owning heritage organisation, in 2011, began a programme of vaccinating badgers against bTB on its Killerton Estate in Devon. Most of the estate is farmed by 18 tenant farmers, who thus have a strong interest in the Trust's approach, particularly as all have felt the effects of the disease. This article reports on a study of the attitudes to vaccination of badgers and to the alternative of a culling programme, using face-to-face interviews with 14 of the tenants. The results indicated first that the views of the respondents were more nuanced than the contemporary public debate about badger control would suggest. Secondly, the attitude of the interviewees to vaccination of badgers against bTB was generally one of resigned acceptance. Thirdly, most respondents would prefer a combination of an effective vaccination programme with an effective culling programme, the latter reducing population of density sufficiently (and preferably targeting the badgers most likely to be diseased) for vaccination to have a reasonable chance of success. While based on a small sample, these results will contribute to the vigorous debate concerning contrasting policy approaches to bTB control in England, Wales and Northern Ireland.

  16. PLGA particulate subunit tuberculosis vaccines promote humoral and Th17 responses but do not enhance control of Mycobacterium tuberculosis infection

    PubMed Central

    Parumasivam, Thaigarajan; Chan, John Gar Yan; Lin, Leon C. W.; Flórido, Manuela; West, Nicholas P.; Chan, Hak-Kim; Britton, Warwick J.

    2018-01-01

    Tuberculosis places a staggering burden on human health globally. The new World Health Organisation End-TB Strategy has highlighted the urgent need for more effective TB vaccines to improve control of the disease. Protein-based subunit vaccines offer potential as safe and effective generators of protective immunity, and the use of particulate vaccine formulation and delivery by the pulmonary route may enhance local immunogenicity. In this study, novel particulate subunit vaccines were developed utilising biodegradable poly(lactic-co-glycolic acid) (PLGA) slow-release particles as carriers for the Mycobacterium tuberculosis lipoprotein MPT83, together with the adjuvants trehalose-dibehenate (TDB) or Monophosphoryl lipid A (MPL). Following delivery by the pulmonary or subcutaneous routes, the immunogenicity and protective efficacy of these vaccines were assessed in a murine model of M. tuberculosis infection. When delivered peripherally, these vaccines induced modest, antigen-specific Th1 and Th17 responses, but strong anti-MPT83 antibody responses. Mucosal delivery of the PLGA(MPT83) vaccine, with or without TDB, increased antigen-specific Th17 responses in the lungs, however, PLGA-encapsulated vaccines did not provide protection against M. tuberculosis challenge. By contrast, peripheral delivery of DDA liposomes containing MPT83 and TDB or MPL, stimulated both Th1 and Th17 responses and generated protection against M. tuberculosis challenge. Therefore, PLGA-formulated vaccines primarily stimulate strong humoral immunity, or Th17 responses if used mucosally, and may be a suitable carrier for vaccines against extracellular pathogens. This study emphasises the critical nature of the vaccine carrier, adjuvant and route of delivery for optimising vaccine efficacy against TB. PMID:29554138

  17. Dengue 4 Vaccine Development

    DTIC Science & Technology

    1987-09-01

    and monkeys. b) Preparation of a production seed from uncloned Dengue 4 (H241) PDK-35 vaccine isolated from viremic serum of a volunteer vaccinee , and...essentially eradicated from the United States and other developed countries, principally as a result of mass vaccination with the trivalent Sabin...CopU~1C FftE 0~AD( ) DENGUE 4 VACCINE DEVELOPMENT Lf 0, to ANNUAL AND FINAL REPORT0 by 0Nyven J. Marchette, Ph.D. September 1, 1987 (For the period 1

  18. Prioritizing vaccines for developing world diseases.

    PubMed

    Saul, Allan; O'Brien, Katherine L

    2017-01-20

    A major disparity in the burden of health will need to be addressed to achieve the "Grand Convergence" by 2035. In particular people living in low and middle income countries have a much higher burden of infectious diseases. Although vaccines have been very effective in reducing the global burden of infectious disease, there are no registered vaccines to address 60% of the current burden of infectious disease, especially in developing countries. Thus there is a pressing need for new vaccines and for prioritizing vaccine development given that resources for developing new vaccines are strictly limited. As part of the GLOBAL HEALTH 2035: Mission Grand Convergence meeting one working group assessed the SMART vaccine algorithm as a mechanism for prioritizing vaccine development for diseases of priority in the developing world. In particular, the working group considered which criteria in the standard SMART set were considered "key" criteria and whether other criteria should be considered, when prioritizing vaccines for this important set of countries. Copyright © 2016. Published by Elsevier Ltd.

  19. What We Have Learned and What We Have Missed in Tuberculosis Pathophysiology for a New Vaccine Design: Searching for the "Pink Swan".

    PubMed

    Cardona, Pere-Joan

    2017-01-01

    This is a call to encourage the search for a new vaccine to stop the progression of Mycobacterium tuberculosis infection to tuberculosis (TB) disease. TB is a highly discreet and stigmatized disease, with a massive impact on human health. It has killed 1.2 billion people in the last 200 years and still kills 1.5 million people per year. Over the last 20 years, the TB vaccine field has experienced spectacular developments, and we have learned about (1) the importance of the Th1 response in controlling infection, mainly against RD1 and Ag85 antigens; (2) the stability of the antigenic repertoire; (3) the dynamics of M. tuberculosis granulomas; or (4) the link between typical and atypical pulmonary TB and the immune status of the host. However, we still do not (1) know how to avoid M. tuberculosis infection and reinfection; (2) understand the major role of the increase in lesion size in progression from infection to disease; (3) the role of interlobular septa in encapsulating pulmonary lesions; or (4) the role of neutrophilic infiltration and an exaggerated inflammatory response in the development of TB disease. These are strong reasons to pursue new, imaginative proposals involving both the antibody response and a balanced, tolerant immune response that averts progression toward TB. So far, the scientific mindset has been quite monolithic and has mainly focused on the stimulation of conventional T cells. But this approach has failed. For that reason, we are seeking unconventional perspectives to find a "pink swan," a more efficacious and safer vaccine candidate.

  20. Evaluation of the Mycobacterium tuberculosis SO2 vaccine using a natural tuberculosis infection model in goats.

    PubMed

    Bezos, J; Casal, C; Álvarez, J; Roy, A; Romero, B; Rodríguez-Bertos, A; Bárcena, C; Díez, A; Juste, R; Gortázar, C; Puentes, E; Aguiló, N; Martín, C; de Juan, L; Domínguez, L

    2017-05-01

    The development of new vaccines against animal tuberculosis (TB) is a priority for improving the control and eradication of this disease, particularly in those species not subjected to compulsory eradication programmes. In this study, the protection conferred by the Mycobacterium tuberculosis SO 2 experimental vaccine was evaluated using a natural infection model in goats. Twenty-six goats were distributed in three groups: (1) 10 goats served as a control group; (2) six goats were subcutaneously vaccinated with BCG; and (3) 10 goats were subcutaneously vaccinated with SO 2 . Four months after vaccination, all groups were merged with goats infected with Mycobacterium bovis or Mycobacterium caprae, and tested over a 40 week period using a tuberculin intradermal test and an interferon-γ assay for mycobacterial reactivity. The severity of lesions was determined at post-mortem examination and the bacterial load in tissues were evaluated by culture. The two vaccinated groups had significantly lower lesion and bacterial culture scores than the control group (P<0.05); at the end of the study, the SO 2 vaccinated goats had the lowest lesion and culture scores. These results suggest that the SO 2 vaccine provides some protection against TB infection acquired from natural exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Prime-boost bacillus Calmette-Guérin vaccination with lentivirus-vectored and DNA-based vaccines expressing antigens Ag85B and Rv3425 improves protective efficacy against Mycobacterium tuberculosis in mice.

    PubMed

    Xu, Ying; Yang, Enzhuo; Wang, Jianguang; Li, Rui; Li, Guanghua; Liu, Guoyuan; Song, Na; Huang, Qi; Kong, Cong; Wang, Honghai

    2014-10-01

    To prevent the global spread of tuberculosis (TB), more effective vaccines and vaccination strategies are urgently needed. As a result of the success of bacillus Calmette-Guérin (BCG) in protecting children against miliary and meningeal TB, the majority of individuals will have been vaccinated with BCG; hence, boosting BCG-primed immunity will probably be a key component of future vaccine strategies. In this study, we compared the ability of DNA-, protein- and lentiviral vector-based vaccines that express the antigens Ag85B and Rv3425 to boost the effects of BCG in the context of immunity and protection against Mycobacterium tuberculosis in C57BL/6 mice. Our results demonstrated that prime-boost BCG vaccination with a lentiviral vector expressing the antigens Ag85B and Rv3425 significantly enhanced immune responses, including T helper type 1 and CD8(+) cytotoxic T lymphocyte responses, compared with DNA- and protein-based vaccines. However, lentivirus-vectored and DNA-based vaccines greatly improved the protective efficacy of BCG against M. tuberculosis, as indicated by a lack of weight loss and significantly reduced bacterial loads and histological damage in the lung. Our study suggests that the use of lentiviral or DNA vaccines containing the antigens Ag85B and Rv3425 to boost BCG is a good choice for the rational design of an efficient vaccination strategy against TB. © 2014 John Wiley & Sons Ltd.

  2. Safety and Immunogenicity of Adenovirus 35 Tuberculosis Vaccine Candidate in Adults with Active or Previous Tuberculosis. A Randomized Trial.

    PubMed

    van Zyl-Smit, Richard N; Esmail, Aliasgar; Bateman, Mary E; Dawson, Rodney; Goldin, Jonathan; van Rikxoort, Eva; Douoguih, Macaya; Pau, Maria Grazia; Sadoff, Jerald C; McClain, J Bruce; Snowden, Margaret Ann; Benko, Jacqueline; Hokey, David A; Rutkowski, Kathryn Tucker; Graves, Andrew; Shepherd, Barbara; Ishmukhamedov, Sadritdin; Kagina, Benjamin M N; Abel, Brian; Hanekom, Willem A; Scriba, Thomas J; Bateman, Eric D

    2017-05-01

    Administration of tuberculosis (TB) vaccines in participants with previous or current pulmonary TB may have the potential for causing harmful postvaccination immunologic (Koch-type) reactions. To assess the safety and immunogenicity of three dose levels of the AERAS-402 live, replication-deficient adenovirus 35-vectored TB candidate vaccine, containing three mycobacterial antigens, in individuals with current or previous pulmonary TB. We performed a phase II randomized, placebo-controlled, double-blinded dose-escalation study in an HIV-negative adult South African cohort (n = 72) with active pulmonary TB (on treatment for 1-4 mo) or pulmonary TB treated at least 12 months before study entry and considered cured. Safety endpoints included clinical assessment, flow volume curves, diffusing capacity of the lung for carbon monoxide, pulse oximetry, chest radiograph, and high-resolution thoracic computerized tomography scans. Cytokine expression by CD4 and CD8 T cells, after stimulation with Ag85A, Ag85B, and TB10.4 peptide pools, was examined by intracellular cytokine staining. No apparent temporal or dose-related changes in clinical status (specifically acute, Koch phenomenon-like reactions), lung function, or radiology attributable to vaccine were observed. Injection site reactions were mild or moderate. Hematuria (by dipstick only) occurred in 25 (41%) of 61 AERAS-402 recipients and 3 (27%) of 11 placebo recipients, although no gross hematuria was reported. AERAS-402 induced robust CD8 + and moderate CD4 + T-cell responses, mainly to Ag85B in both vaccine groups. Administration of the AERAS-402 candidate TB vaccine to participants with current or previous pulmonary TB induced a robust immune response and is not associated with clinically significant pulmonary complications. Clinical trial registered with www.clinicaltrials.gov (NCT 02414828) and in the South African National Clinical Trials Register ( www.sanctr.gov.za DOH 27-0808-2060).

  3. Impact of BRICS’ investment in vaccine development on the global vaccine market

    PubMed Central

    Milstien, Julie; Schmitt, Sarah

    2014-01-01

    Abstract Brazil, the Russian Federation, India, China and South Africa – the countries known as BRICS – have made considerable progress in vaccine production, regulation and development over the past 20 years. In 1993, all five countries were producing vaccines but the processes used were outdated and non-standardized, there was little relevant research and there was negligible international recognition of the products. By 2014, all five countries had strong initiatives for the development of vaccine technology and had greatly improved their national regulatory capacity. South Africa was then the only BRICS country that was not completely producing vaccines. South Africa is now in the process of re-establishing its own vaccine production and passing beyond the stage of simply importing, formulating and filling vaccine bulks. Changes in the public sector’s price per dose of selected vaccines, the global market share represented by products from specific manufacturers, and the attractiveness, for multinational companies, of partnership and investment opportunities in BRICS companies have all been analysed. The results indicate that the BRICS countries have had a major impact on vaccine price and availability, with much of that impact attributable to the output of Indian vaccine manufacturers. China is expected to have a greater impact soon, given the anticipated development of Chinese vaccine manufacturers in the near future. BRICS’ accomplishments in the field of vaccine development are expected to reshape the global vaccine market and accelerate access to vaccines in the developing world. The challenge is to turn these expectations into strategic actions and practical outcomes. PMID:24940018

  4. Impact of BRICS' investment in vaccine development on the global vaccine market.

    PubMed

    Kaddar, Miloud; Milstien, Julie; Schmitt, Sarah

    2014-06-01

    Brazil, the Russian Federation, India, China and South Africa--the countries known as BRICS--have made considerable progress in vaccine production, regulation and development over the past 20 years. In 1993, all five countries were producing vaccines but the processes used were outdated and non-standardized, there was little relevant research and there was negligible international recognition of the products. By 2014, all five countries had strong initiatives for the development of vaccine technology and had greatly improved their national regulatory capacity. South Africa was then the only BRICS country that was not completely producing vaccines. South Africa is now in the process of re-establishing its own vaccine production and passing beyond the stage of simply importing, formulating and filling vaccine bulks. Changes in the public sector's price per dose of selected vaccines, the global market share represented by products from specific manufacturers, and the attractiveness, for multinational companies, of partnership and investment opportunities in BRICS companies have all been analysed. The results indicate that the BRICS countries have had a major impact on vaccine price and availability, with much of that impact attributable to the output of Indian vaccine manufacturers. China is expected to have a greater impact soon, given the anticipated development of Chinese vaccine manufacturers in the near future. BRICS' accomplishments in the field of vaccine development are expected to reshape the global vaccine market and accelerate access to vaccines in the developing world. The challenge is to turn these expectations into strategic actions and practical outcomes.

  5. Tuberculin reactivity in bacille Calmette-Guérin vaccinated populations: a compilation of international data.

    PubMed

    Joos, T J; Miller, W C; Murdoch, D M

    2006-08-01

    The effect of previously administered bacille Calmette-Guérin (BCG) vaccine on subsequent tuberculin skin tests (TSTs) complicates screening for latent tuberculosis infection (LTBI) in foreign-born persons. To determine the usefulness of the TST as a screening test for LTBI in foreign-born persons. A literature search was performed of published studies that compared tuberculin reactivity amongst BCG-vaccinated and non-vaccinated groups. The percentages of positive reactors in the two groups were then used to calculate a prevalence ratio. The prevalence ratio varied with the age of the groups tested and the incidence of TB in their countries of origin. The TST performed poorly in vaccinated persons of all ages from countries of low TB incidence, but was a useful screen for LTBI in vaccinated adults from countries of high and intermediate incidence. The test performed poorly as a screening method for vaccinated children under 2 years of age. Its usefulness in vaccinated children aged 2-14 years varied considerably. The usefulness of the TST as a screening method for LTBI depends on the age of the patient and the incidence of TB in their country of origin.

  6. Prime-boost BCG vaccination with DNA vaccines based in β-defensin-2 and mycobacterial antigens ESAT6 or Ag85B improve protection in a tuberculosis experimental model

    PubMed Central

    Cervantes-Villagrana, Alberto R.; Hernández-Pando, Rogelio; Biragyn, Arya; Castañeda-Delgado, Julio; Bodogai, Monica; Martínez-Fierro, Margarita; Sada, Eduardo; Trujillo, Valentin; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno

    2018-01-01

    The World Health Organization (WHO) has estimated that there are about 8 million new cases annually of active Tuberculosis (TB). Despite its irregular effectiveness (0–89%), the Bacillus Calmette-Guérin) BCG is the only vaccine available worldwide for prevention of TB; thus, the design is important of novel and more efficient vaccination strategies. Considering that β-defensin-2 is an antimicrobial peptide that induces dendritic cell maturation through the TLR-4 receptor and that both ESAT-6 and Ag85B are immunodominant mycobacterial antigens and efficient activators of the protective immune response, we constructed two DNA vaccines by the fusion of the gene encoding β-defensin-2 and antigens ESAT6 (pDE) and 85B (pDA). After confirming efficient local antigen expression that induced high and stable Interferon gamma (IFN-γ) production in intramuscular (i.m.) vaccinated Balb/c mice, groups of mice were vaccinated with DNA vaccines in a prime-boost regimen with BCG and with BCG alone, and 2 months later were challenged with the mild virulence reference strain H37Rv and the highly virulent clinical isolate LAM 5186. The level of protection was evaluated by survival, lung bacilli burdens, and extension of tissue damage (pneumonia). Vaccination with both DNA vaccines showed similar protection to that of BCG. After the challenge with the highly virulent Mycobacterium tuberculosis strain, animals that were prime-boosted with BCG and then boosted with both DNA vaccines showed significant higher survival and less tissue damage than mice vaccinated only with BCG. These results suggest that improvement of BCG vaccination, such as the prime-boost DNA vaccine, represents a more efficient vaccination scheme against TB. PMID:23196205

  7. Prime-boost BCG vaccination with DNA vaccines based in β-defensin-2 and mycobacterial antigens ESAT6 or Ag85B improve protection in a tuberculosis experimental model.

    PubMed

    Cervantes-Villagrana, Alberto R; Hernández-Pando, Rogelio; Biragyn, Arya; Castañeda-Delgado, Julio; Bodogai, Monica; Martínez-Fierro, Margarita; Sada, Eduardo; Trujillo, Valentin; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno

    2013-01-11

    The World Health Organization (WHO) has estimated that there are about 8 million new cases annually of active Tuberculosis (TB). Despite its irregular effectiveness (0-89%), the Bacillus Calmette-Guérin) BCG is the only vaccine available worldwide for prevention of TB; thus, the design is important of novel and more efficient vaccination strategies. Considering that β-defensin-2 is an antimicrobial peptide that induces dendritic cell maturation through the TLR-4 receptor and that both ESAT-6 and Ag85B are immunodominant mycobacterial antigens and efficient activators of the protective immune response, we constructed two DNA vaccines by the fusion of the gene encoding β-defensin-2 and antigens ESAT6 (pDE) and 85B (pDA). After confirming efficient local antigen expression that induced high and stable Interferon gamma (IFN-γ) production in intramuscular (i.m.) vaccinated Balb/c mice, groups of mice were vaccinated with DNA vaccines in a prime-boost regimen with BCG and with BCG alone, and 2 months later were challenged with the mild virulence reference strain H37Rv and the highly virulent clinical isolate LAM 5186. The level of protection was evaluated by survival, lung bacilli burdens, and extension of tissue damage (pneumonia). Vaccination with both DNA vaccines showed similar protection to that of BCG. After the challenge with the highly virulent Mycobacterium tuberculosis strain, animals that were prime-boosted with BCG and then boosted with both DNA vaccines showed significant higher survival and less tissue damage than mice vaccinated only with BCG. These results suggest that improvement of BCG vaccination, such as the prime-boost DNA vaccine, represents a more efficient vaccination scheme against TB. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. [BCG vaccines for the prevention of tuberculosis in the world].

    PubMed

    Hashimoto, T

    1997-11-01

    The BCG vaccines will celebrate the 100th anniversary of their discovery in a decade at the beginning of the next century since Albert Calmette and Camille Guerin had presented it before the Academie des Sciences in 1908. At present tuberculosis kills more people than any other infectious disease about 3 million people a year, including almost 300,000 children under 15, and is producing over 7,000 deaths and over 24,000 new cases every day. Therefore, WHO declared a global health emergency in 1993. More worse, recently multi-drug resistant tubercle bacilli are emerging rapidly making TB patients incurable. Under these situations we need a potent anti-tuberculosis vaccine. So first of all, we must check the century-old BCG before proceeding further. At moment, the BCG vaccines are being used worldwide in the largest quantities in the world, but still most controversial vaccines anywhere. I would like to describe here their success and failure in the combat against the white plague. 1. The Expanded Programme on Immunization (EPI). In 1974, when the EPI was launched by WHO, less than 5% of the world children were immunized against six infectious diseases including tuberculosis. In 1995 statistics, BCG gave the highest vaccination coverage, 87% higher than any other 5 vaccines of EPI for children. The BCG in EPI must have saved a lot of infants as the vaccine, has been proved to be most effective against the blood-born tuberculosis of child type. 2. The efficacy of BCG vaccination against tuberculosis. Results of each 10 of randomized controlled trials (RCT) and Case-control studies (CCS) showed the protective efficacy against tuberculosis as uncertain, unpredictable, as protective efficacy varied from 80% to 0%. More recently, a Meta-analysis of selected papers on BCG field trials which were so far collected. They recalculated vaccine protective effect separately for pulmonary TB and for meningeal/miliary TB in the trials. As the result, it was found that protective

  9. Field Trial of an Aerially-Distributed Tuberculosis Vaccine in a Low-Density Wildlife Population of Brushtail Possums (Trichosurus vulpecula).

    PubMed

    Nugent, Graham; Yockney, Ivor J; Whitford, E Jackie; Cross, Martin L; Aldwell, Frank E; Buddle, Bryce M

    2016-01-01

    Oral-delivery Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine in a lipid matrix has been shown to confer protection against M. bovis infection and reduce the severity of tuberculosis (TB) when fed to brushtail possums (Trichosurus vulpecula), the major wildlife vector of bovine TB in New Zealand. Here we demonstrate the feasibility of aerial delivery of this live vaccine in bait form to an M. bovis-infected wild possum population, and subsequently assess vaccine uptake and field efficacy. Pre-trial studies indicated a resident possum population at very low density (<0.6 possums/ha) at the field site, with a 5.1% prevalence of macroscopic TB lesions. Pilot studies indicated that flavoured lipid matrix baits in weather-proof sachets could be successfully sown aerially via helicopter and were palatable to, and likely to be consumed by, a majority of wild possums under free-choice conditions. Subsequently, sachet-held lipid baits containing live BCG vaccine were sown at 3 baits/ha over a 1360 ha area, equating to >5 baits available per possum. Blood sampling conducted two months later provided some evidence of vaccine uptake. A necropsy survey conducted one year later identified a lower prevalence of culture-confirmed M. bovis infection and/or gross TB lesions among adult possums in vaccinated areas (1.1% prevalence; 95% CI, 0-3.3%, n = 92) than in unvaccinated areas (5.6%; 0.7-10.5%, n = 89); P = 0.098. Although not statistically different, the 81% efficacy in protecting possums against natural infection calculated from these data is within the range of previous estimates of vaccine efficacy in trials where BCG vaccine was delivered manually. We conclude that, with further straightforward refinement to improve free-choice uptake, aerial delivery of oral BCG vaccine is likely to be effective in controlling TB in wild possums. We briefly discuss contexts in which this could potentially become an important complementary tool in achieving national eradication

  10. Field Trial of an Aerially-Distributed Tuberculosis Vaccine in a Low-Density Wildlife Population of Brushtail Possums (Trichosurus vulpecula)

    PubMed Central

    Nugent, Graham; Yockney, Ivor J.; Whitford, E. Jackie; Cross, Martin L.; Aldwell, Frank E.; Buddle, Bryce M.

    2016-01-01

    Oral-delivery Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine in a lipid matrix has been shown to confer protection against M. bovis infection and reduce the severity of tuberculosis (TB) when fed to brushtail possums (Trichosurus vulpecula), the major wildlife vector of bovine TB in New Zealand. Here we demonstrate the feasibility of aerial delivery of this live vaccine in bait form to an M. bovis-infected wild possum population, and subsequently assess vaccine uptake and field efficacy. Pre-trial studies indicated a resident possum population at very low density (<0.6 possums/ha) at the field site, with a 5.1% prevalence of macroscopic TB lesions. Pilot studies indicated that flavoured lipid matrix baits in weather-proof sachets could be successfully sown aerially via helicopter and were palatable to, and likely to be consumed by, a majority of wild possums under free-choice conditions. Subsequently, sachet-held lipid baits containing live BCG vaccine were sown at 3 baits/ha over a 1360 ha area, equating to >5 baits available per possum. Blood sampling conducted two months later provided some evidence of vaccine uptake. A necropsy survey conducted one year later identified a lower prevalence of culture-confirmed M. bovis infection and/or gross TB lesions among adult possums in vaccinated areas (1.1% prevalence; 95% CI, 0–3.3%, n = 92) than in unvaccinated areas (5.6%; 0.7–10.5%, n = 89); P = 0.098. Although not statistically different, the 81% efficacy in protecting possums against natural infection calculated from these data is within the range of previous estimates of vaccine efficacy in trials where BCG vaccine was delivered manually. We conclude that, with further straightforward refinement to improve free-choice uptake, aerial delivery of oral BCG vaccine is likely to be effective in controlling TB in wild possums. We briefly discuss contexts in which this could potentially become an important complementary tool in achieving national

  11. [Development of new vaccines].

    PubMed

    González-Romo, Fernando; Picazo, Juan J

    2015-10-01

    Recent and important advances in the fields of immunology, genomics, functional genomics, immunogenetics, immunogenomics, bioinformatics, microbiology, genetic engineering, systems biology, synthetic biochemistry, proteomics, metabolomics and nanotechnology, among others, have led to new approaches in the development of vaccines. The better identification of ideal epitopes, the strengthening of the immune response due to new adjuvants, and the search of new routes of vaccine administration, are good examples of advances that are already a reality and that will favour the development of more vaccines, their use in indicated population groups, or its production at a lower cost. There are currently more than 130 vaccines are under development against the more wished (malaria or HIV), difficult to get (CMV or RSV), severe re-emerging (Dengue or Ebola), increasing importance (Chagas disease or Leishmania), and nosocomial emerging (Clostridium difficile or Staphylococcus aureus) infectious diseases. Copyright © 2015. Published by Elsevier España, S.L.U.

  12. Global gene transcriptome analysis in vaccinated cattle revealed a dominant role of IL-22 for protection against bovine tuberculosis.

    PubMed

    Bhuju, Sabin; Aranday-Cortes, Elihu; Villarreal-Ramos, Bernardo; Xing, Zhou; Singh, Mahavir; Vordermeier, H Martin

    2012-12-01

    Bovine tuberculosis (bTB) is a chronic disease of cattle caused by Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex group of bacteria. Vaccination of cattle might offer a long-term solution for controlling the disease and priority has been given to the development of a cattle vaccine against bTB. Identification of biomarkers in tuberculosis research remains elusive and the goal is to identify host correlates of protection. We hypothesized that by studying global gene expression we could identify in vitro predictors of protection that could help to facilitate vaccine development. Calves were vaccinated with BCG or with a heterologous BCG prime adenovirally vectored subunit boosting protocol. Protective efficacy was determined after M. bovis challenge. RNA was prepared from PPD-stimulated PBMC prepared from vaccinated-protected, vaccinated-unprotected and unvaccinated control cattle prior to M. bovis challenge and global gene expression determined by RNA-seq. 668 genes were differentially expressed in vaccinated-protected cattle compared with vaccinated-unprotected and unvaccinated control cattle. Cytokine-cytokine receptor interaction was the most significant pathway related to this dataset with IL-22 expression identified as the dominant surrogate of protection besides INF-γ. Finally, the expression of these candidate genes identified by RNA-seq was evaluated by RT-qPCR in an independent set of PBMC samples from BCG vaccinated and unvaccinated calves. This experiment confirmed the importance of IL-22 as predictor of vaccine efficacy.

  13. Parenteral Vaccination with Heat-Inactivated Mycobacterium Bovis Reduces the Prevalence of Tuberculosis-Compatible Lesions in Farmed Wild Boar.

    PubMed

    Díez-Delgado, I; Rodríguez, O; Boadella, M; Garrido, J M; Sevilla, I A; Bezos, J; Juste, R; Domínguez, L; Gortázar, C

    2017-10-01

    In 2012, a wild boar (Sus scrofa) tuberculosis (TB) control programme was set up in a wild boar farm by means of intramuscular (IM) vaccination with a heat-inactivated Mycobacterium bovis vaccine (IV). The goal was to assess safety and efficacy of the parenterally administered IV in a large farm setting with natural M. bovis circulation. Based on preceding results under laboratory conditions, we hypothesized that vaccinated piglets would show smaller scores of TB-compatible lesions (TBCL) than unvaccinated controls. After vaccination, no adverse reactions were detected by visual inspection or at post-mortem examination (n = 668 and 97, respectively). Post-mortem data on TBCL were available for 97 vaccinated wild boar and 182 controls. The observed TBCL prevalence was 4.1% (95% CI = 0.2-8%) and 12.1% (95% CI = 7.1-17.1%) for vaccinated and control wild boar, respectively (P < 0.05). Among those animals with TBCL, no difference in the mean lesion score was found (P > 0.05). The results show that IV administered intramuscularly to wild boar piglets is safe and protects vaccinated individuals (66% reduction in TBCL prevalence) against natural challenge in a low-prevalence setting. In a context of increasing TB prevalence in wild boar in Mediterranean habitats, vaccination achieved a progressive though slow decline in lesion prevalence since the onset of the vaccination scheme. Hence, vaccination might contribute, along with other tools, to TB control in wild boar and in pigs. © 2016 Blackwell Verlag GmbH.

  14. Dengue vaccine development: strategies and challenges.

    PubMed

    Ramakrishnan, Lakshmy; Pillai, Madhavan Radhakrishna; Nair, Radhakrishnan R

    2015-03-01

    Infection with dengue virus may result in dengue fever or a more severe outcome, such as dengue hemorrhagic syndrome/shock. Dengue virus infection poses a threat to endemic regions for four reasons: the presence of four serotypes, each with the ability to cause a similar disease outcome, including fatality; difficulties related to vector control; the lack of specific treatment; and the nonavailability of a suitable vaccine. Vaccine development is considered challenging due to the severity of the disease observed in individuals who have acquired dengue-specific immunity, either passively or actively. Therefore, the presence of vaccine-induced immunity against a particular serotype may prime an individual to severe disease on exposure to dengue virus. Vaccine development strategies include live attenuated vaccines, chimeric, DNA-based, subunit, and inactivated vaccines. Each of the candidates is in various stages of preclinical and clinical development. Issues pertaining to selection pressures, viral interaction, and safety still need to be evaluated in order to induce a complete protective immune response against all four serotypes. This review highlights the various strategies that have been employed in vaccine development, and identifies the obstacles to producing a safe and effective vaccine.

  15. The WHO's new End TB Strategy in the post-2015 era of the Sustainable Development Goals.

    PubMed

    Lönnroth, Knut; Raviglione, Mario

    2016-03-01

    The WHO's new End TB Strategy 2016-2035 has evolved from previous global strategies to respond to old and new challenges and take advantage of new opportunities. It frames the global fight against TB as a development, social justice and human rights issue, while re-emphasizing the public health and clinical fundaments of TB care and prevention. In this commentary, we outline how TB prevention, care and control will both benefit from and contribute to the achievement of the new Sustainable Development Goals that were recently adopted at the United Nations. © The author 2016. The World Health Organization has granted Oxford University Press permission for the reproduction of this article.

  16. Status of vaccine research and development of vaccines for malaria.

    PubMed

    Birkett, Ashley J

    2016-06-03

    Despite recent progress in reducing deaths attributable to malaria, it continues to claim approximately 500,000 lives per year and is associated with approximately 200 million infections. New tools, including safe and effective vaccines, are needed to ensure that the gains of the last 15 years are leveraged toward achieving the ultimate goal of malaria parasite eradication. In 2015, the European Medicines Agency announced the adoption of a positive opinion for the malaria vaccine candidate most advanced in development, RTS,S/AS01, which provides modest protection against clinical malaria; in early 2016, WHO recommended large-scale pilot implementations of RTS,S in settings of moderate-to-high malaria transmission. In alignment with these advancements, the community goals and preferred product characteristics for next-generation vaccines have been updated to inform the development of vaccines that are highly efficacious in preventing clinical malaria, and those needed to accelerate parasite elimination. Next-generation vaccines, targeting all stages of the parasite lifecycle, are in early-stage development with the most advanced in Phase 2 trials. Importantly, progress is being made in the definition of feasible regulatory pathways to accelerate timelines, including for vaccines designed to interrupt transmission of parasites from humans to mosquitoes. The continued absence of financially lucrative, high-income markets to drive investment in malaria vaccine development points to continued heavy reliance on public and philanthropic funding. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  17. PPD-induced monocyte mitochondrial damage is associated with a protective effect to develop tuberculosis in BCG vaccinated individuals: A cohort study.

    PubMed

    Marín, Diana; Marín, Nancy; Del Corral, Helena; López, Lucelly; Ramirez-Agudelo, María Elena; Rojas, Carlos A; Arbeláez, María P; García, Luis F; Rojas, Mauricio

    2017-01-01

    The mechanisms of mononuclear phagocyte death have been associated with the permissiveness and resistance to mycobacterial replication, but it remains unknown whether or not they help predict the risk of developing TB. To describe the factors associated with the induction of monocyte mitochondrial and membrane damage in response to PPD as well as determine if this type of damage might predict the susceptibility of developing active tuberculosis in a cohort of household contacts (HHCs) from Medellin, Colombia from 2005 to 2008. The prospective cohort study contains 2060 HHCs patients with pulmonary tuberculosis who were meticulously followed for two years. A survey of the socio-demographic, clinical, epidemiological factors and blood samples were collected. Mononuclear cell cultures were stimulated with or without PPD and the type of monocyte death was determined by the flow of cytometry, an indicator was also used for its analysis. Logistic regression was adjusted by the Generalized Estimations Equations and the survival was estimated with the Kaplan-Meier and Cox regression. Confidence intervals were used for estimating the association. 1,859 out of 2,060 blood samples of the HHCs patients analyzed showed monocyte death. In response to PPD, 83.4% underwent mitochondrial damage while 50.9% had membrane damage. The membrane damage in response to PPD was higher in children under 4 years (OR: 1.57; (95% CI: 1.1 to 2.4) and the HHCs who slept regularly in the same household has an index case of (OR: 1.54; 95% CI: 1.0 to 2.3). After adjustment by age, comorbidities, nutritional status, proximity to index case and overcrowding, the risk of developing active TB among BCG vaccinated HHCs individuals with induction of mitochondrial damage was HR = 0.19 (95% CI: 0.1 to 0.5). The induction of monocytes mitochondrial damage by PPD stimulation correlates with protection of TB disease development in BCG-vaccinated HHCs. This represents a potential tool to predict susceptibility

  18. Identifying ethical issues in the development of vaccines and in vaccination.

    PubMed

    Johari, Veena

    2017-01-01

    Vaccines are a widely accepted public health intervention. They are also a profitable tool for pharmaceutical companies manufacturing vaccines. There are many vaccines in the pipeline, for various diseases, or as combination vaccines for several diseases. However, there is also a growing concern about vaccines and the manner in which they are developed and approved by the authorities. Approvals are fast tracked and adverse events and serious adverse events following vaccination are seldom reported once the vaccine gets its marketing approval. Thus, vaccines have been clouded with many controversies and their use as a public health tool to prevent diseases is constantly under challenge.

  19. Immunotherapy of tuberculosis with Mycobacterium leprae Hsp65 as a DNA vaccine triggers cross-reactive antibodies against mammalian Hsp60 but not pathological autoimmunity.

    PubMed

    Doimo, Nayara T S; Zárate-Bladés, Carlos R; Rodrigues, Rodrigo F; Tefé-Silva, Cristiane; Trotte, Marcele N S; Souza, Patrícia R M; Soares, Luana S; Rios, Wendy M; Floriano, Elaine M; Brandão, Izaira T; Masson, Ana P; Coelho, Verônica; Ramos, Simone G; Silva, Celio L

    2014-01-01

    Despite substantial efforts in recent years toward the development of new vaccines and drugs against tuberculosis (TB), success has remained elusive. Immunotherapy of TB with mycobacterial Hsp65 as a DNA vaccine (DNA-hsp65) results in a reduction of systemic bacterial loads and lung tissue damage, but the high homology of Hsp65 with the mammalian protein raises concern that pathological autoimmune responses may also be triggered. We searched for autoimmune responses elicited by DNA-hsp65 immunotherapy in mice chronically infected with TB by evaluating the humoral immune response and comprehensive histopathology using stereology. Cross-reactive antibodies between mycobacterial and mammalian Hsp60/65 were detected; however, no signs of pathological autoimmunity were found up to 60 days after the end of the therapy.

  20. Cellular immune response in MDR-TB patients to different protein expression of MDR and susceptible Mycobacterium tuberculosis: Rv0147, a novel MDR-TB biomarker.

    PubMed

    Hadizadeh Tasbiti, Alireza; Yari, Shamsi; Siadat, Seyed Davar; Tabarsi, Payam; Saeedfar, Kayvan; Yari, Fatemeh

    2018-02-01

    Tuberculosis (TB) is a crucial public health problem with prevalence of multidrug resistant (MDR) rising. An accurate TB biomarker is urgently needed to monitor the response to treatment in patients with MDR tuberculosis. To analyze interaction between selected MDR-TB purified protein and immune cells, dendritic cells from MDR-TB patients and healthy subjects were stimulated by 55KDa protein fractions (Rv0147). The purified proteins identified by proteomic techniques (two-dimensional gel electrophoresis, mass spectrometry) and peptide sequences are known to bind a MHC class I alleles which are extracted from the Immune Epitope Database and Analysis Resource database ( www.iedb.org ). T cells were isolated from PBMC by negative selection and cells were cultured in RPMI-1640 at 37 °C and 5% CO 2 . Cell culture was assayed for cytokine IL-10 and INF-γ by ELISA. We found that INF-γ production was significantly (335 ± 35.5 pg/ml, P ˂ 0.05) upregulated after protein candidate (Rv0147) stimulation by dendritic cells from MDR-TB patients, whereas IL-10 production was greatly reduced compared with production in healthy subjects (212 ± 9.94 pg/ml, P ˂ 0.05). In fact, the purified protein, Rv0147, stimulated dendritic cells from MDR-TB patients, failed to produce IL-10 and directly stimulates INF-γ production by T cells. These results suggest that the purified protein, Rv0147, may stimulate Th1 type protective cytokine response in MDR-TB patients but not in normal subjects. The production of INF-γ but not IL-10 in the presence of purified protein, Rv0147, may be shifted to Th1 responses in MDR-TB patients and supports its potential as protein vaccine candidates against TB.

  1. Collaborative vaccine development: partnering pays.

    PubMed

    Ramachandra, Rangappa

    2008-01-01

    Vaccine development, supported by infusions of public and private venture capital, is re-entering a golden age as one of the fastest growing sectors in the life-sciences industry. Demand is driven by great unmet need in underdeveloped countries, increased resistance to current treatments, bioterrorism, and for prevention indications in travelers, pediatric, and adult diseases. Production systems are becoming less reliant on processes such as egg-based manufacturing, while new processes can help to optimize vaccines. Expeditious development hinges on efficient study conduct, which is greatly enhanced through research partnerships with specialized contract research organizations (CROs) that are licensed and knowledgeable in the intricacies of immunology and with the technologic and scientific foundation to support changing timelines and strategies inherent to vaccine development. The CRO often brings a more objective assessment for probability of success and may offer alternative development pathways. Vaccine developers are afforded more flexibility and are free to focus on innovation and internal core competencies. Functions readily outsourced to a competent partner include animal model development, safety and efficacy studies, immunotoxicity and immunogenicity, dose response studies, and stability and potency testing. These functions capitalize on the CRO partner's regulatory and scientific talent and expertise, and reduce infrastructure expenses for the vaccine developer. Successful partnerships result in development efficiencies, elimination or reduced redundancies, and improved time to market. Keys to success include honest communications, transparency, and flexibility.

  2. What We Have Learned and What We Have Missed in Tuberculosis Pathophysiology for a New Vaccine Design: Searching for the “Pink Swan”

    PubMed Central

    Cardona, Pere-Joan

    2017-01-01

    This is a call to encourage the search for a new vaccine to stop the progression of Mycobacterium tuberculosis infection to tuberculosis (TB) disease. TB is a highly discreet and stigmatized disease, with a massive impact on human health. It has killed 1.2 billion people in the last 200 years and still kills 1.5 million people per year. Over the last 20 years, the TB vaccine field has experienced spectacular developments, and we have learned about (1) the importance of the Th1 response in controlling infection, mainly against RD1 and Ag85 antigens; (2) the stability of the antigenic repertoire; (3) the dynamics of M. tuberculosis granulomas; or (4) the link between typical and atypical pulmonary TB and the immune status of the host. However, we still do not (1) know how to avoid M. tuberculosis infection and reinfection; (2) understand the major role of the increase in lesion size in progression from infection to disease; (3) the role of interlobular septa in encapsulating pulmonary lesions; or (4) the role of neutrophilic infiltration and an exaggerated inflammatory response in the development of TB disease. These are strong reasons to pursue new, imaginative proposals involving both the antibody response and a balanced, tolerant immune response that averts progression toward TB. So far, the scientific mindset has been quite monolithic and has mainly focused on the stimulation of conventional T cells. But this approach has failed. For that reason, we are seeking unconventional perspectives to find a “pink swan,” a more efficacious and safer vaccine candidate. PMID:28555137

  3. Current and developing therapies for the treatment of multi drug resistant tuberculosis (MDR-TB) in India.

    PubMed

    Muniyandi, Malaisamy; Ramachandran, Rajeswari

    2017-09-01

    India accounts for 25% of the global burden of MDR-TB. In 2016, the India's Revised National TB Control Programme reported a success rate of 46% among 19,298 MDR-TB patients treated under the programme. This suboptimal treatment outcome warrants an urgent need for newer drugs and newer regimens in the treatment of MDR-TB. India requires new shorter, cheap, safe and effective anti-TB regimen to treat MDR-TB. Areas covered: We used different search strategies to obtain relevant literature from PubMed, on Indian experiences of developing therapies for the treatment of MDR-TB. Further information from the Central TB Division Government of India on programmatic management of resistant TB was collected. Expert opinion: In 2016 WHO recommended a shorter MDR-TB regimen of 9-12 months (4-6 Km-Mfx-Pto-Cfz-Z-Hhigh-dose-E /5 Mfx-Cfz-Z-E) may be used instead of longer regimens. Currently, conducting trials involving newer drugs such as bedaquiline, have been proposed. The regimen will be of a shorter duration containing isoniazid, prothionamide, bedaquiline, levofloxacin, ciprofloxacin, ethambutol and pyrazinamide (STREAM regimen). To successfully treat MDR-TB one requires new classes of antibiotic and newer diagnostic tests. This represents an enormous financial and technical challenge to the programme managers and policy makers.

  4. Learning from epidemiological, clinical, and immunological studies on Mycobacterium africanum for improving current understanding of host-pathogen interactions, and for the development and evaluation of diagnostics, host-directed therapies, and vaccines for tuberculosis.

    PubMed

    Zumla, Alimuddin; Otchere, Isaac Darko; Mensah, Gloria Ivy; Asante-Poku, Adwoa; Gehre, Florian; Maeurer, Markus; Bates, Matthew; Mwaba, Peter; Ntoumi, Francine; Yeboah-Manu, Dorothy

    2017-03-01

    Mycobacterium africanum comprises two phylogenetic lineages within the Mycobacterium tuberculosis complex (MTBC). M. africanum was first described and isolated in 1968 from the sputum of a Senegalese patient with pulmonary tuberculosis (TB) and it has been identified increasingly as an important cause of human TB, particularly prevalent in West Africa. The restricted geographical distribution of M. africanum, in contrast to the widespread global distribution of other species of MTBC, requires explanation. Available data indicate that M. africanum may also have important differences in transmission, pathogenesis, and host-pathogen interactions, which could affect the evaluation of new TB intervention tools (diagnostics and vaccines)-those currently in use and those under development. The unequal geographical distribution and spread of MTBC species means that individual research findings from one country or region cannot be generalized across the continent. Thus, generalizing data from previous and ongoing research studies on MTBC may be inaccurate and inappropriate. A major rethink is required regarding the design and structure of future clinical trials of new interventions. The West, Central, East, and Southern African EDCTP Networks of Excellence provide opportunities to take forward these pan-Africa studies. More investments into molecular, epidemiological, clinical, diagnostic, and immunological studies across the African continent are required to enable further understanding of host-M. africanum interactions, leading to the development of more specific diagnostics, biomarkers, host-directed therapies, and vaccines for TB. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

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

    PubMed

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

    2011-04-20

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

  6. Use of Prior Vaccinations for the Development of New Vaccines

    NASA Astrophysics Data System (ADS)

    Etlinger, H. M.; Gillessen, D.; Lahm, H.-W.; Matile, H.; Schonfeld, H.-J.; Trzeciak, A.

    1990-07-01

    There is currently a need for vaccine development to improve the immunogenicity of protective epitopes, which themselves are often poorly immunogenic. Although the immunogenicity of these epitopes can be enhanced by linking them to highly immunogenic carriers, such carriers derived from current vaccines have not proven to be generally effective. One reason may be related to epitope-specific suppression, in which prior vaccination with a protein can inhibit the antibody response to new epitopes linked to the protein. To circumvent such inhibition, a peptide from tetanus toxoid was identified that, when linked to a B cell epitope and injected into tetanus toxoid-primed recipients, retained sequences for carrier but not suppressor function. The antibody response to the B cell epitope was enhanced. This may be a general method for taking advantage of previous vaccinations in the development of new vaccines.

  7. Clinical and economic impact of a specific BCG vaccination program implemented in Prato, central Italy, involving foreign newborns on hospitalizations.

    PubMed

    Bellini, Irene; Nastasi, Antonino; Boccalini, Sara

    2016-09-01

    In Tuscany (Central Italy), the average annual notification rate of tuberculosis (TB) in the years 2007-2012 was 7.5-9.8 per 100,000 people, with the Local Health Unit of Prato (LHU4) showing the highest rate compared to the other regional area. Therefore, in order to reduce the burden of TB, foreign newborns in the LHU4 are being given the Bacillus Calmette-Guérin (BCG) vaccine since 2000. The aim of this study is to assess the impact of BCG vaccination in Prato, in terms of TB-related hospitalizations and costs. The regional archive containing all TB-related discharges and costs in the period 2007-2014 was consulted. Data regarding foreigners living in the LHU4 who have been vaccinated since 2000 were compared with those living in the other Tuscan LHUs and never vaccinated. These populations were then disaggregated by a threshold age of 15 y. After calculating the standardized hospitalization rates, the expected number of hospitalizations for TB among unvaccinated adults (in both populations) was found to be similar in the LHU4 and the other LHUs (165 vs. 156). However, expected number of hospitalizations among children in the other Tuscan LHUs (67) was double that of the LHU4 (34). If the same vaccine had been administrated everywhere, each year 29 hospitalizations could have been avoided and EUR 343,525 saved. Overall, BCG vaccinations cost EUR 14,879 in the LHU4, but 69 hospitalizations were avoided and EUR 107,435 saved. The introduction of the BCG immunization program in the LHU4 of Prato has led to significant reductions in the clinical and economic impact of TB.

  8. Priorities for CMV vaccine development

    PubMed Central

    Krause, Philip R.; Bialek, Stephanie R.; Boppana, Suresh B.; Griffiths, Paul D.; Laughlin, Catherine A.; Ljungman, Per; Mocarski, Edward S.; Pass, Robert F.; Read, Jennifer S.; Schleiss, Mark R.; Plotkin, Stanley A.

    2015-01-01

    A multidisciplinary meeting addressed priorities related to development of vaccines against cytomegalovirus (CMV), the cause of congenital CMV (cCMV) disease and of serious disease in the immunocompromised. Participants discussed optimal uses of a CMV vaccine, aspects of clinical study design, and the value of additional research. A universal childhood CMV vaccine could potentially rapidly reduce cCMV disease, as infected children are sources of viral transmission to seronegative and seropositive mothers. A vaccine administered to adolescents or adult women could also reduce cCMV disease by making them immune prior to pregnancy. Clinical trials of CMV vaccines in women should evaluate protection against cCMV infection, an essential precursor of cCMV disease, which is a more practical and acceptable endpoint for assessing vaccine effects on maternal-fetal transmission. Clinical trials of vaccines to evaluate prevention of CMV disease in stem cell transplant recipients could use CMV viremia at a level triggering preemptive antiviral therapy as an endpoint, because widespread use of preemptive and prophylactic antivirals has rendered CMV-induced disease too rare to be a practical endpoint for clinical trials. In solid organ transplant patients, CMV-associated disease is sufficiently common for use as a primary endpoint. Additional research to advance CMV vaccine development should include identifying factors that predict fetal loss due to CMV, determining age-specific incidence and transmission rates, defining the mechanism and relative contributions of maternal reactivation and re-infection to cCMV disease, developing assays that can distinguish between reactivation and re-infection in seropositive vaccinees, further defining predictors of sequelae from cCMV infection, and identifying clinically relevant immune response parameters to CMV (including developing validated assays that could assess CMV antibody avidity) that could lead to the establishment of immune

  9. Treatment: Latent TB Infection (LTBI) and TB Disease

    MedlinePlus

    ... Search Form Controls Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  10. Developing an effective breast cancer vaccine.

    PubMed

    Soliman, Hatem

    2010-07-01

    Harnessing the immune response in treating breast cancer would potentially offer a less toxic, more targeted approach to eradicating residual disease. Breast cancer vaccines are being developed to effectively train cytotoxic T cells to recognize and kill transformed cells while sparing normal ones. However, achieving this goal has been problematic due to the ability of established cancers to suppress and evade the immune response. A review of the literature on vaccines and breast cancer treatment was conducted, specifically addressing strategies currently available, as well as appropriate settings, paradigms for vaccine development and response monitoring, and challenges with immunosuppression. Multiple issues need to be addressed in order to optimize the benefits offered by breast cancer vaccines. Primary issues include the following: (1) cancer vaccines will likely work better in a minimal residual disease state, (2) clinical trial design for immunotherapy should incorporate recommendations from expert groups such as the Cancer Vaccine Working Group and use standardized immune response measurements, (3) the presently available cancer vaccine approaches, including dendritic cell-based, tumor-associated antigen peptide-based, and whole cell-based, have various pros and cons, (4) to date, no one approach has been shown to be superior to another, and (5) vaccines will need to be combined with immunoregulatory agents to overcome tumor-related immunosuppression. Combining a properly optimized cancer vaccine with novel immunomodulating agents that overcome tumor-related immunosuppression in a well-designed clinical trial offers the best hope for developing an effective breast cancer vaccine strategy.

  11. A Promising Listeria-Vectored Vaccine Induces Th1-Type Immune Responses and Confers Protection Against Tuberculosis.

    PubMed

    Yin, Yuelan; Lian, Kai; Zhao, Dan; Tao, Chengwu; Chen, Xiang; Tan, Weijun; Wang, Xiaobo; Xu, Zhengzhong; Hu, Maozhi; Rao, Yan; Zhou, Xiaohui; Pan, Zhiming; Zhang, Xiaoming; Jiao, Xin'an

    2017-01-01

    Deaths associated with tuberculosis (TB) is rising and accounted for 1.4 million deaths in 2015 many of which were due to drug-resistant bacteria. Vaccines represent an important medical intervention, but the current Bacilli Calmette-Guerin (BCG) vaccine is not ideal for the protection of teenagers and adults. Therefore, a safe and effective vaccine is urgently needed. In this study, we designed a novel vaccine using an attenuated Listeria monocytogenes strain carrying fusion antigen FbpB-ESAT-6 (rLM) and characterized its safety and protective efficacy against Mycobacterium tuberculosis ( M.tb ) infection in mice. Compared to the wild type strain yzuLM4 and parental strain LMΔ actA/plcB (LM1-2), the virulence of rLM was significantly reduced as judged by its infectious kinetics and LD 50 dose. Further characterization of intravenous immunization showed that prime-boost vaccination significantly increased the levels of Th1 cytokines (IFN-γ, IL-17, and IL-6), and enhanced cytotoxic T lymphocyte (CTL) CTLs activity, suggesting that rLM could elicit potent Th1/Th17 responses. More importantly, rLM significantly conferred the protection against M.tb H37Rv challenge. Collectively, our findings indicated that rLM is a novel and useful tool to prevent M.tb infection, and can be potentially be used to boost BCG-primed immunity.

  12. A Multistage Subunit Vaccine Effectively Protects Mice Against Primary Progressive Tuberculosis, Latency and Reactivation.

    PubMed

    Ma, Jilei; Teng, Xindong; Wang, Xiaochun; Fan, Xionglin; Wu, Yaqi; Tian, Maopeng; Zhou, Zijie; Li, Longmeng

    2017-08-01

    Adult tuberculosis (TB) is the main cause of TB epidemic and death. The infection results mainly by endogenous reactivation of latent TB infection and secondarily transmitted by exogenous infection. There is no vaccine for adult TB. To this end, we first chose antigens from a potential antigenic reservoir. The antigens strongly recognized T cells from latent and active TB infections that responded to antigens expressed by Mycobacterium tuberculosis cultured under different metabolic states. Fusions of single-stage polyprotein CTT3H, two-stage polyprotein A1D4, and multistage CMFO were constructed. C57BL/6 mice vaccinated with DMT adjuvant ed CMFO (CMFO-DMT) were protected more significantly than by CTT3H-DMT, and efficacy was similar to that of the only licensed vaccine, Bacillus Calmette-Guérin (BCG) and A1D4-DMT in the M. tuberculosis primary infection model. In the setting of BCG priming and latent TB infection, M. tuberculosis in the lung and spleen was eliminated more effectively in mice boosted with CMFO-DMT rather than with BCG, A1D4-DMT, or CTT3H-DMT. In particular, sterile immunity was only conferred by CMFO-DMT, which was associated with expedited homing of interferon-gamma + CD4 + T EM and interleukin-2 + T CM cells from the spleen to the infected lung. CMFO-DMT represents a promising candidate to prevent the occurrence of adult TB through both prophylactic and therapeutic methods, and warrants assessment in preclinical and clinical trials. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  13. Progress in Brucella vaccine development

    PubMed Central

    YANG, Xinghong; SKYBERG, Jerod A.; CAO, Ling; CLAPP, Beata; THORNBURG, Theresa; PASCUAL, David W.

    2012-01-01

    Brucella spp. are zoonotic, facultative intracellular pathogens, which cause animal and human disease. Animal disease results in abortion of fetuses; in humans, it manifests flu-like symptoms with an undulant fever, with osteoarthritis as a common complication of infection. Antibiotic regimens for human brucellosis patients may last several months and are not always completely effective. While there are no vaccines for humans, several licensed live Brucella vaccines are available for use in livestock. The performance of these animal vaccines is dependent upon the host species, dose, and route of immunization. Newly engineered live vaccines, lacking well-defined virulence factors, retain low residual virulence, are highly protective, and may someday replace currently used animal vaccines. These also have possible human applications. Moreover, due to their enhanced safety and efficacy in animal models, subunit vaccines for brucellosis show great promise for their application in livestock and humans. This review summarizes the progress of brucellosis vaccine development and presents an overview of candidate vaccines. PMID:23730309

  14. Status of vaccine research and development of vaccines for herpes simplex virus.

    PubMed

    Johnston, Christine; Gottlieb, Sami L; Wald, Anna

    2016-06-03

    Herpes simplex virus type-1 (HSV-1) and -2 (HSV-2) are highly prevalent global pathogens which commonly cause recurrent oral and genital ulcerations. Less common but more serious complications include meningitis, encephalitis, neonatal infection, and keratitis. HSV-2 infection is a significant driver of the HIV epidemic, increasing the risk of HIV acquisition 3 fold. As current control strategies for genital HSV-2 infection, including antiviral therapy and condom use, are only partially effective, vaccines will be required to reduce infection. Both preventive and therapeutic vaccines for HSV-2 are being pursued and are in various stages of development. We will provide an overview of efforts to develop HSV-2 vaccines, including a discussion of the clinical need for an HSV vaccine, and status of research and development with an emphasis on recent insights from trials of vaccine candidates in clinical testing. In addition, we will touch upon aspects of HSV vaccine development relevant to low and middle income countries. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  15. Advances and challenges in malaria vaccine development.

    PubMed

    Crompton, Peter D; Pierce, Susan K; Miller, Louis H

    2010-12-01

    Malaria caused by Plasmodium falciparum remains a major public health threat, especially among children and pregnant women in Africa. An effective malaria vaccine would be a valuable tool to reduce the disease burden and could contribute to elimination of malaria in some regions of the world. Current malaria vaccine candidates are directed against human and mosquito stages of the parasite life cycle, but thus far, relatively few proteins have been studied for potential vaccine development. The most advanced vaccine candidate, RTS,S, conferred partial protection against malaria in phase II clinical trials and is currently being evaluated in a phase III trial in Africa. New vaccine targets need to be identified to improve the chances of developing a highly effective malaria vaccine. A better understanding of the mechanisms of naturally acquired immunity to malaria may lead to insights for vaccine development.

  16. Vaccine Development for Zika Virus-Timelines and Strategies.

    PubMed

    Durbin, Anna P

    2016-09-01

    Zika virus is a mosquito-borne Flavivirus that spread rapidly through South and Central America in 2015 to 2016. Microcephaly has been causally associated with Zika virus infection during pregnancy and the World Health Organization declared Zika virus as a Public Health Emergency of International Concern. To address this crisis, many groups have expressed their commitment to developing a Zika virus vaccine. Different strategies for Zika virus vaccine development are being considered including recombinant live attenuated vaccines, purified inactivated vaccines (PIVs), DNA vaccines, and viral vectored vaccines. Important to Zika virus vaccine development will be the target group chosen for vaccination and which end point(s) is chosen for efficacy determination. The first clinical trials of Zika virus vaccine candidates will begin in Q3/4 2016 but the pathway to licensure for a Zika virus vaccine is expected to take several years. Efforts are ongoing to accelerate Zika virus vaccine development and evaluation with the ultimate goal of reducing time to licensure. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  17. Advances in HIV-1 Vaccine Development

    PubMed Central

    Gao, Yong

    2018-01-01

    An efficacious HIV-1 vaccine is regarded as the best way to halt the ongoing HIV-1 epidemic. However, despite significant efforts to develop a safe and effective vaccine, the modestly protective RV144 trial remains the only efficacy trial to provide some level of protection against HIV-1 acquisition. This review will outline the history of HIV vaccine development, novel technologies being applied to HIV vaccinology and immunogen design, as well as the studies that are ongoing to advance our understanding of vaccine-induced immune correlates of protection. PMID:29614779

  18. Vaxjo: a web-based vaccine adjuvant database and its application for analysis of vaccine adjuvants and their uses in vaccine development.

    PubMed

    Sayers, Samantha; Ulysse, Guerlain; Xiang, Zuoshuang; He, Yongqun

    2012-01-01

    Vaccine adjuvants are compounds that enhance host immune responses to co-administered antigens in vaccines. Vaxjo is a web-based central database and analysis system that curates, stores, and analyzes vaccine adjuvants and their usages in vaccine development. Basic information of a vaccine adjuvant stored in Vaxjo includes adjuvant name, components, structure, appearance, storage, preparation, function, safety, and vaccines that use this adjuvant. Reliable references are curated and cited. Bioinformatics scripts are developed and used to link vaccine adjuvants to different adjuvanted vaccines stored in the general VIOLIN vaccine database. Presently, 103 vaccine adjuvants have been curated in Vaxjo. Among these adjuvants, 98 have been used in 384 vaccines stored in VIOLIN against over 81 pathogens, cancers, or allergies. All these vaccine adjuvants are categorized and analyzed based on adjuvant types, pathogens used, and vaccine types. As a use case study of vaccine adjuvants in infectious disease vaccines, the adjuvants used in Brucella vaccines are specifically analyzed. A user-friendly web query and visualization interface is developed for interactive vaccine adjuvant search. To support data exchange, the information of vaccine adjuvants is stored in the Vaccine Ontology (VO) in the Web Ontology Language (OWL) format.

  19. Vaxjo: A Web-Based Vaccine Adjuvant Database and Its Application for Analysis of Vaccine Adjuvants and Their Uses in Vaccine Development

    PubMed Central

    Sayers, Samantha; Ulysse, Guerlain; Xiang, Zuoshuang; He, Yongqun

    2012-01-01

    Vaccine adjuvants are compounds that enhance host immune responses to co-administered antigens in vaccines. Vaxjo is a web-based central database and analysis system that curates, stores, and analyzes vaccine adjuvants and their usages in vaccine development. Basic information of a vaccine adjuvant stored in Vaxjo includes adjuvant name, components, structure, appearance, storage, preparation, function, safety, and vaccines that use this adjuvant. Reliable references are curated and cited. Bioinformatics scripts are developed and used to link vaccine adjuvants to different adjuvanted vaccines stored in the general VIOLIN vaccine database. Presently, 103 vaccine adjuvants have been curated in Vaxjo. Among these adjuvants, 98 have been used in 384 vaccines stored in VIOLIN against over 81 pathogens, cancers, or allergies. All these vaccine adjuvants are categorized and analyzed based on adjuvant types, pathogens used, and vaccine types. As a use case study of vaccine adjuvants in infectious disease vaccines, the adjuvants used in Brucella vaccines are specifically analyzed. A user-friendly web query and visualization interface is developed for interactive vaccine adjuvant search. To support data exchange, the information of vaccine adjuvants is stored in the Vaccine Ontology (VO) in the Web Ontology Language (OWL) format. PMID:22505817

  20. Immunotherapy of tuberculosis with Mycobacterium leprae Hsp65 as a DNA vaccine triggers cross-reactive antibodies against mammalian Hsp60 but not pathological autoimmunity

    PubMed Central

    Doimo, Nayara TS; Zárate-Bladés, Carlos R; Rodrigues, Rodrigo F; Tefé-Silva, Cristiane; Trotte, Marcele NS; Souza, Patrícia RM; Soares, Luana S; Rios, Wendy M; Floriano, Elaine M; Brandão, Izaira T; Masson, Ana P; Coelho, Verônica; Ramos, Simone G; Silva, Celio L

    2014-01-01

    Despite substantial efforts in recent years toward the development of new vaccines and drugs against tuberculosis (TB), success has remained elusive. Immunotherapy of TB with mycobacterial Hsp65 as a DNA vaccine (DNA-hsp65) results in a reduction of systemic bacterial loads and lung tissue damage, but the high homology of Hsp65 with the mammalian protein raises concern that pathological autoimmune responses may also be triggered. We searched for autoimmune responses elicited by DNA-hsp65 immunotherapy in mice chronically infected with TB by evaluating the humoral immune response and comprehensive histopathology using stereology. Cross-reactive antibodies between mycobacterial and mammalian Hsp60/65 were detected; however, no signs of pathological autoimmunity were found up to 60 days after the end of the therapy. PMID:24607935

  1. A single dose of a DNA vaccine encoding apa coencapsulated with 6,6'-trehalose dimycolate in microspheres confers long-term protection against tuberculosis in Mycobacterium bovis BCG-primed mice.

    PubMed

    Carlétti, Dyego; Morais da Fonseca, Denise; Gembre, Ana Flávia; Masson, Ana Paula; Weijenborg Campos, Lívia; Leite, Luciana C C; Rodrigues Pires, Andréa; Lannes-Vieira, Joseli; Lopes Silva, Célio; Bonato, Vânia Luiza Deperon; Horn, Cynthia

    2013-08-01

    Mycobacterium bovis BCG prime DNA (Mycobacterium tuberculosis genes)-booster vaccinations have been shown to induce greater protection against tuberculosis (TB) than BCG alone. This heterologous prime-boost strategy is perhaps the most realistic vaccination for the future of TB infection control, especially in countries where TB is endemic. Moreover, a prime-boost regimen using biodegradable microspheres seems to be a promising immunization to stimulate a long-lasting immune response. The alanine proline antigen (Apa) is a highly immunogenic glycoprotein secreted by M. tuberculosis. This study investigated the immune protection of Apa DNA vaccine against intratracheal M. tuberculosis challenge in mice on the basis of a heterologous prime-boost regimen. BALB/c mice were subcutaneously primed with BCG and intramuscularly boosted with a single dose of plasmid carrying apa and 6,6'-trehalose dimycolate (TDM) adjuvant, coencapsulated in microspheres (BCG-APA), and were evaluated 30 and 70 days after challenge. This prime-boost strategy (BCG-APA) resulted in a significant reduction in the bacterial load in the lungs, thus leading to better preservation of the lung parenchyma, 70 days postinfection compared to BCG vaccinated mice. The profound effect of this heterologous prime-boost regimen in the experimental model supports its development as a feasible strategy for prevention of TB.

  2. Vaccines: From Empirical Development to Rational Design

    PubMed Central

    Rueckert, Christine; Guzmán, Carlos A.

    2012-01-01

    Infectious diseases are responsible for an overwhelming number of deaths worldwide and their clinical management is often hampered by the emergence of multi-drug-resistant strains. Therefore, prevention through vaccination currently represents the best course of action to combat them. However, immune escape and evasion by pathogens often render vaccine development difficult. Furthermore, most currently available vaccines were empirically designed. In this review, we discuss why rational design of vaccines is not only desirable but also necessary. We introduce recent developments towards specifically tailored antigens, adjuvants, and delivery systems, and discuss the methodological gaps and lack of knowledge still hampering true rational vaccine design. Finally, we address the potential and limitations of different strategies and technologies for advancing vaccine development. PMID:23144616

  3. Challenges of Vaccine Development for Zika Virus.

    PubMed

    Blackman, Marcia A; Kim, In-Jeong; Lin, Jr-Shiuan; Thomas, Stephen J

    2018-03-01

    The emergence of outbreaks of Zika virus (ZIKV) in Brazil in 2015 was associated with devastating effects on fetal development and prompted a world health emergency and multiple efforts to generate an effective vaccine against infection. There are now more than 40 vaccine candidates in preclinical development and six in clinical trials. Despite similarities with other flaviviruses to which successful vaccines have been developed, such as yellow fever virus and Japanese Encephalitis virus, there are unique challenges to the development and clinical trials of a vaccine for ZIKV.

  4. Potential Benefits of Cattle Vaccination as a Supplementary Control for Bovine Tuberculosis

    PubMed Central

    Conlan, Andrew J. K.; Brooks Pollock, Ellen; McKinley, Trevelyan J.; Mitchell, Andrew P.; Jones, Gareth J.; Vordermeier, Martin; Wood, James L. N.

    2015-01-01

    Vaccination for the control of bovine tuberculosis (bTB) in cattle is not currently used within any international control program, and is illegal within the EU. Candidate vaccines, based upon Mycobacterium bovis bacillus Calmette-Guérin (BCG) all interfere with the action of the tuberculin skin test, which is used to determine if animals, herds and countries are officially bTB-free. New diagnostic tests that Differentiate Infected from Vaccinated Animals (DIVA) offer the potential to introduce vaccination within existing eradication programs. We use within-herd transmission models estimated from historical data from Great Britain (GB) to explore the feasibility of such supplemental use of vaccination. The economic impact of bovine Tuberculosis for farmers is dominated by the costs associated with testing, and associated restrictions on animal movements. Farmers’ willingness to adopt vaccination will require vaccination to not only reduce the burden of infection, but also the risk of restrictions being imposed. We find that, under the intensive sequence of testing in GB, it is the specificity of the DIVA test, rather than the sensitivity, that is the greatest barrier to see a herd level benefit of vaccination. The potential negative effects of vaccination could be mitigated through relaxation of testing. However, this could potentially increase the hidden burden of infection within Officially TB Free herds. Using our models, we explore the range of the DIVA test characteristics necessary to see a protective herd level benefit of vaccination. We estimate that a DIVA specificity of at least 99.85% and sensitivity of >40% is required to see a protective benefit of vaccination with no increase in the risk of missed infection. Data from experimentally infected animals suggest that this target specificity could be achieved in vaccinates using a cocktail of three DIVA antigens while maintaining a sensitivity of 73.3% (95%CI: 61.9, 82.9%) relative to post

  5. Development of Streptococcus agalactiae vaccines for tilapia.

    PubMed

    Liu, Guangjin; Zhu, Jielian; Chen, Kangming; Gao, Tingting; Yao, Huochun; Liu, Yongjie; Zhang, Wei; Lu, Chengping

    2016-12-21

    Vaccination is a widely accepted and effective method to prevent most pathogenic diseases in aquaculture. Various species of tilapia, especially Nile tilapia Oreochromis niloticus, are farmed worldwide because of their high consumer demand. Recently, the tilapia-breeding industry has been hampered by outbreaks of Streptococcus agalactiae infection, which cause high mortality and huge economic losses. Many researchers have attempted to develop effective S. agalactiae vaccines for tilapia. This review provides a summary of the different kinds of S. agalactiae vaccines for tilapia that have been developed recently. Among the various vaccine types, inactivated S. agalactiae vaccines showed superior protection efficiency when compared with live attenuated, recombinant and DNA vaccines. With respect to vaccination method, injecting the vaccine into tilapia provided the most effective immunoprotection. Freund's incomplete adjuvant appeared to be suitable for tilapia vaccines. Other factors, such as immunization duration and number, fish size and challenge dose, also influenced the vaccine efficacy.

  6. Development of vaccines against meningococcal disease.

    PubMed

    Jódar, Luis; Feavers, Ian M; Salisbury, David; Granoff, Dan M

    2002-04-27

    Neisseria meningitidis is a major cause of bacterial meningitis and sepsis. Polysaccharide-protein conjugate vaccines for prevention of group C disease have been licensed in Europe. Such vaccines for prevention of disease caused by groups A (which is associated with the greatest disease burden worldwide), Y, and W135 are being developed. However, conventional approaches to develop a vaccine for group B strains, which are responsible for most cases in Europe and the USA, have been largely unsuccessful. Capsular polysaccharide-based vaccines can elicit autoantibodies to host polysialic acid, whereas the ability of most non-capsular antigens to elicit broad-based immunity is limited by their antigenic diversity. Many new membrane proteins have been discovered during analyses of genomic sequencing data. These antigens are highly conserved and, in mice, elicit serum bactericidal antibodies, which are the serological hallmark of protective immunity in man. Therefore, there are many promising new vaccine candidates, and improved prospects for development of a broadly protective vaccine for group B disease, and for control of all meningococcal disease.

  7. TB Terms

    MedlinePlus

    ... Search Form Controls Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  8. TB in healthcare workers in the UK: a cohort analysis 2009-2013.

    PubMed

    Davidson, Jennifer A; Lalor, Maeve K; Anderson, Laura F; Tamne, Surinder; Abubakar, Ibrahim; Thomas, H Lucy

    2017-07-01

    To describe the burden of TB in healthcare workers (HCWs) in the UK and determine whether HCWs are at increased risk of TB due to occupational exposure. Retrospective cohort analysis of national UK TB surveillance and genotyping data between 2009 and 2013. The rate of TB in HCWs compared with non-HCWs to calculate incidence rate ratios stratified by country of birth. 2320 cases of TB in HCWs were notified in the study period, 85% were born abroad. The TB rate in HCWs was 23.4 (95% CI 22.5 to 24.4) per 100 000 compared with 16.2 (95% CI 16.0 to 16.3) per 100 000 in non-HCWs. After stratifying by country of birth, there was not an increased TB incidence in HCWs for the majority of countries of birth, including in the UK-born. Using combined genotyping and epidemiological data, only 10 confirmed nosocomial transmission events involving HCWs were identified between 2010 and 2012. Of these, only two involved transmission to patients. The lack of an increased risk of TB after stratifying by country of birth, and the very few transmission events involving nosocomial transmission in the UK suggests that TB in HCWs in the UK is not generally acquired through UK occupational exposure. The majority of cases in foreign-born HCWs are likely to result from reactivation of latent TB infection (LTBI) acquired abroad, and is not likely to be prevented by BCG vaccination in the UK. Testing and treatment of LTBI in HCWs with exposure to high TB burden countries should be the focus of occupational health prevention activities. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  9. Deletion of nuoG from the Vaccine Candidate Mycobacterium bovis BCG ΔureC::hly Improves Protection against Tuberculosis

    PubMed Central

    Gengenbacher, Martin; Nieuwenhuizen, Natalie; Vogelzang, Alexis; Liu, Haipeng; Kaiser, Peggy; Schuerer, Stefanie; Lazar, Doris; Wagner, Ina; Mollenkopf, Hans-Joachim

    2016-01-01

    ABSTRACT The current tuberculosis (TB) vaccine, Mycobacterium bovis Bacillus Calmette-Guérin (BCG), provides insufficient protection against pulmonary TB. Previously, we generated a listeriolysin-expressing recombinant BCG strain, which to date has successfully completed phase I and phase IIa clinical trials. In an attempt to further improve efficacy, we deleted the antiapoptotic virulence gene nuoG, encoding NADH dehydrogenase 1 subunit G, from BCG ΔureC::hly. In vitro, deletion of nuoG unexpectedly led to strongly increased recruitment of the autophagosome marker LC3 to the engulfed vaccine, suggesting that nuoG also affects xenophagic pathways. In mice, BCG ΔureC::hly ΔnuoG vaccination was safer than BCG and improved protection over that of parental BCG ΔureC::hly, significantly reducing TB load in murine lungs, ameliorating pulmonary pathology, and enhancing immune responses. Transcriptome analysis of draining lymph nodes after vaccination with either BCG ΔureC::hly or BCG ΔureC::hly ΔnuoG demonstrated earlier and stronger induction of immune responses than that with BCG SSI and suggested upregulation of inflammasome activation and interferon-induced GTPases. In summary, BCG ΔureC::hly ΔnuoG is a promising next-generation TB vaccine candidate with excellent efficacy and safety. PMID:27222470

  10. Vaccines against enteric infections for the developing world

    PubMed Central

    Czerkinsky, Cecil; Holmgren, Jan

    2015-01-01

    Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors: —limited knowledge regarding the properties of the gut immune system during early life;—lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines;—lack of correlates/surrogates of mucosal immune protection; and—limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries.There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world's poorest, confer long-term protection and herd immunity, and must be able to contain epidemics. PMID:25964464

  11. MPT-51/CpG DNA vaccine protects mice against Mycobacterium tuberculosis.

    PubMed

    Silva, Bruna Daniella de Souza; da Silva, Ediane Batista; do Nascimento, Ivan Pereira; Dos Reis, Michelle Cristina Guerreiro; Kipnis, André; Junqueira-Kipnis, Ana Paula

    2009-07-16

    Tuberculosis (TB) is a severe infectious disease that kills approximately two million people worldwide every year. Because BCG protection is variable and does not protects adults, there is a great need for a new vaccine against TB that does not represent a risk for immunocompromised patients and that is also capable of protecting adult individuals. MPT-51 is a protein found in the genome of mycobacteria and binds to the fibronectin of the extracellular matrix, which may have a role in host tissue attachment and virulence. In order to test the usefulness of MPT-51 as a subunit vaccine, BALB/c were vaccinated and challenged with Mycobacterium tuberculosis. The infection of BALB/c with M. tuberculosis increased the number of IFN-gamma(+) T lymphocytes specific to MPT-51 in the spleen and lungs. Inoculation with rMPT-51/FIA and with rMPT-51/CpG DNA in non-infected BALB/c increased the amounts of IFN-gamma(+) T lymphocytes. Inoculation with rMPT-51/FIA also induced a humoral response specific to MPT-51. CFU counts of lung tissues done 60 days after infection showed a reduction of about 2 log in the bacteria load in the group of animals inoculated with rMPT-51/CpG DNA. These results make MPT-51 a valuable component to be further evaluated in the development of other subunit vaccines.

  12. Lessons learned from a review of the development of selected vaccines. National Vaccine Advisory Committee.

    PubMed

    Peter, G; des Vignes-Kendrick, M; Eickhoff, T C; Fine, A; Galvin, V; Levine, M M; Maldonado, Y A; Marcuse, E K; Monath, T P; Osborn, J E; Plotkin, S; Poland, G A; Quinlisk, M P; Smith, D R; Sokol, M; Soland, D B; Whitley-Williams, P N; Williamson, D E; Breiman, R F

    1999-10-01

    Although the vaccine research and development network in the United States remains vibrant, its continued success requires maintaining harmonious interaction among its many components. Changing one component is likely to affect the system overall. An examination of case studies of the development of selected vaccines would allow an examination of the network as a whole. This article presents conclusions drawn from the case study review undertaken. Successful development of vaccines is a time-intensive process requiring years of commitment from a network of scientists and a continuum of regulatory and manufacturing entities. We undertook this work to shed light on how well the vaccine development system in the United States performs. The National Vaccine Advisory Committee examined the research and development pathways of several vaccines that reached licensure expeditiously (hepatitis B vaccine, Haemophilus influenzae type b conjugate vaccines); some that became licensed only after considerable delay (oral typhoid Ty21a vaccine, varicella vaccine); some that are at the point of imminent or recent licensure (reassortant Rhesus rotavirus vaccine, which was licensed by the Food and Drug Administration on August 30, 1998) or near submission for licensure (intranasal cold adapted influenza vaccine); and one for which clinical development is slow because of hurdles that must be overcome (respiratory syncytial virus vaccines). Some common themes emerged from the reviews of these vaccine "case histories": the expediting influence of a strong scientific base and rationale; the need for firm quantitation of disease burden and clear identification of target populations; the critical role played by individuals or teams who act as "champions" to overcome the inevitable obstacles; availability of relevant animal models, high-quality reagents and standardized assays to measure immune response; the absolute requirement for well designed, meticulously executed clinical trials of

  13. Communicating vaccine safety during the development and introduction of vaccines.

    PubMed

    Kochhar, Sonali

    2015-01-01

    Vaccines are the best defense available against infectious diseases. Vaccine safety is of major focus for regulatory bodies, vaccine manufacturers, public health authorities, health care providers and the public as vaccines are often given to healthy children and adults as well as to pregnant woman. Safety assessment is critical at all stages of vaccine development. Effective, clear and consistent communication of the risks and benefits of vaccines and advocacy during all stages of clinical research (including the preparation, approvals, conduct of clinical trials through the post marketing phase) is critically important. This needs to be done for all major stakeholders (e.g. community members, Study Team, Health Care Providers, Ministry of Health, Regulators, Ethics Committee members, Public Health Authorities and Policy Makers). Improved stakeholder alignment would help to address some of the concerns that may affect the clinical research, licensing of vaccines and their wide-spread use in immunization programs around the world.

  14. A Single Dose of a DNA Vaccine Encoding Apa Coencapsulated with 6,6′-Trehalose Dimycolate in Microspheres Confers Long-Term Protection against Tuberculosis in Mycobacterium bovis BCG-Primed Mice

    PubMed Central

    Carlétti, Dyego; Morais da Fonseca, Denise; Gembre, Ana Flávia; Masson, Ana Paula; Weijenborg Campos, Lívia; Leite, Luciana C. C.; Rodrigues Pires, Andréa; Lannes-Vieira, Joseli; Lopes Silva, Célio; Bonato, Vânia Luiza Deperon

    2013-01-01

    Mycobacterium bovis BCG prime DNA (Mycobacterium tuberculosis genes)-booster vaccinations have been shown to induce greater protection against tuberculosis (TB) than BCG alone. This heterologous prime-boost strategy is perhaps the most realistic vaccination for the future of TB infection control, especially in countries where TB is endemic. Moreover, a prime-boost regimen using biodegradable microspheres seems to be a promising immunization to stimulate a long-lasting immune response. The alanine proline antigen (Apa) is a highly immunogenic glycoprotein secreted by M. tuberculosis. This study investigated the immune protection of Apa DNA vaccine against intratracheal M. tuberculosis challenge in mice on the basis of a heterologous prime-boost regimen. BALB/c mice were subcutaneously primed with BCG and intramuscularly boosted with a single dose of plasmid carrying apa and 6,6′-trehalose dimycolate (TDM) adjuvant, coencapsulated in microspheres (BCG-APA), and were evaluated 30 and 70 days after challenge. This prime-boost strategy (BCG-APA) resulted in a significant reduction in the bacterial load in the lungs, thus leading to better preservation of the lung parenchyma, 70 days postinfection compared to BCG vaccinated mice. The profound effect of this heterologous prime-boost regimen in the experimental model supports its development as a feasible strategy for prevention of TB. PMID:23740922

  15. [Human resource capacity building on TB laboratory work for TB control program--through the experience of international TB laboratory training course for TB control at the Research Institute of Tuberculosis, JATA, Japan].

    PubMed

    Fujiki, Akiko; Kato, Seiya

    2008-06-01

    The international training course on TB laboratory work for national tuberculosis program (NTP) has been conducted at the Research Institute of Tuberculosis since 1975 funded by Japan International Cooperation Agency in collaboration with WHO Western Pacific Regional Office. The aim of the course is to train key personnel in TB laboratory field for NTP in resource-limited countries. The course has trained 265 national key personnel in TB laboratory service from 57 resource-limited countries in the last 33 years. The number of participants trained may sound too small in the fight against the large TB problem in resource-limited countries. However, every participant is playing an important role as a core and catalyst for the TB control program in his/her own country when they were back home. The curriculum is composed of technical aspects on TB examination, mainly sputum microscopy in addition since microscopy service is provided at many centers that are deployed in a widely spread area, the managerial aspect of maintaining quality TB laboratory work at the field laboratory is another component of the curriculum. Effective teaching methods using materials such as artificial sputum, which is useful for panel slide preparation, and technical manuals with illustrations and pictures of training procedure have been developed through the experience of the course. These manuals are highly appreciated and widely used by the front line TB workers. The course has also contributed to the expansion of EQA (External Quality Assessment) system on AFB microscopy for the improvement of the quality of TB laboratory service of NTP. The course is well-known for not only having a long history, but also for its unique learning method emphasizing "Participatory Training", particularly for practicum sessions to master the skills on AFB microscopy. The method in learning AFB microscopy, which was developed by the course, was published as a training manual by IUATLD, RIT and USAID. As it is

  16. HSV-2 Vaccine: Current Status and Insight into Factors for Developing an Efficient Vaccine

    PubMed Central

    Zhu, Xiao-Peng; Muhammad, Zaka S.; Wang, Jian-Guang; Lin, Wu; Guo, Shi-Kun; Zhang, Wei

    2014-01-01

    Herpes simplex virus type 2 (HSV-2), a globally sexually transmitted virus, and also one of the main causes of genital ulcer diseases, increases susceptibility to HIV-1. Effective vaccines to prevent HSV-2 infection are not yet available, but are currently being developed. To facilitate this process, the latest progress in development of these vaccines is reviewed in this paper. A summary of the most promising HSV-2 vaccines tested in animals in the last five years is presented, including the main factors, and new ideas for developing an effective vaccine from animal experiments and human clinical trials. Experimental results indicate that future HSV-2 vaccines may depend on a strategy that targets mucosal immunity. Furthermore, estradiol, which increases the effectiveness of vaccines, may be considered as an adjuvant. Therefore, this review is expected to provide possible strategies for development of future HSV-2 vaccines. PMID:24469503

  17. [Duties of physicians or other healthcare workers connected with diagnosis, treatment, dissemination of information, assessment and registration of TB patients].

    PubMed

    Zielonka, Tadeusz M

    2015-01-01

    Effective laws provide a series of duties to be performed by physicians and other medical personnel associated with TB. Every TB case and death resulting from TB as well as any case of undesirable result of BCG test requires notification and filling in of a special form. The physician has a duty to inform TB patients their legal guardians, close relatives or friends about the need to undergo sanitary and diagnostic procedure, treatment or vaccination, as well as on how to prevent disease from spreading. Persons failing to comply with the relevant numerous legal requirements in this respect are subject to a fine.TB patients can use special sick benefits extending up to 270 days. There is a requirement to use appropriate codes to define TB irrespective of LCD-10 classification.

  18. Prognostic score to predict mortality during TB treatment in TB/HIV co-infected patients.

    PubMed

    Nguyen, Duc T; Jenkins, Helen E; Graviss, Edward A

    2018-01-01

    Estimating mortality risk during TB treatment in HIV co-infected patients is challenging for health professionals, especially in a low TB prevalence population, due to the lack of a standardized prognostic system. The current study aimed to develop and validate a simple mortality prognostic scoring system for TB/HIV co-infected patients. Using data from the CDC's Tuberculosis Genotyping Information Management System of TB patients in Texas reported from 01/2010 through 12/2016, age ≥15 years, HIV(+), and outcome being "completed" or "died", we developed and internally validated a mortality prognostic score using multiple logistic regression. Model discrimination was determined by the area under the receiver operating characteristic (ROC) curve (AUC). The model's good calibration was determined by a non-significant Hosmer-Lemeshow's goodness of fit test. Among the 450 patients included in the analysis, 57 (12.7%) died during TB treatment. The final prognostic score used six characteristics (age, residence in long-term care facility, meningeal TB, chest x-ray, culture positive, and culture not converted/unknown), which are routinely collected by TB programs. Prognostic scores were categorized into three groups that predicted mortality: low-risk (<20 points), medium-risk (20-25 points) and high-risk (>25 points). The model had good discrimination and calibration (AUC = 0.82; 0.80 in bootstrap validation), and a non-significant Hosmer-Lemeshow test p = 0.71. Our simple validated mortality prognostic scoring system can be a practical tool for health professionals in identifying TB/HIV co-infected patients with high mortality risk.

  19. The development of global vaccine stockpiles

    PubMed Central

    Yen, Catherine; Hyde, Terri B; Costa, Alejandro J; Fernandez, Katya; Tam, John S; Hugonnet, Stéphane; Huvos, Anne M; Duclos, Philippe; Dietz, Vance J; Burkholder, Brenton T

    2016-01-01

    Global vaccine stockpiles, in which vaccines are reserved for use when needed for emergencies or supply shortages, have effectively provided countries with the capacity for rapid response to emergency situations, such as outbreaks of yellow fever and meningococcal meningitis. The high cost and insufficient supply of many vaccines, including oral cholera vaccine and pandemic influenza vaccine, have prompted discussion on expansion of the use of vaccine stockpiles to address a wider range of emerging and re-emerging diseases. However, the decision to establish and maintain a vaccine stockpile is complex and must take account of disease and vaccine characteristics, stockpile management, funding, and ethical concerns, such as equity. Past experience with global vaccine stockpiles provide valuable information about the processes for their establishment and maintenance. In this Review we explored existing literature and stockpile data to discuss the lessons learned and to inform the development of future vaccine stockpiles. PMID:25661473

  20. HIV vaccines: new frontiers in vaccine development.

    PubMed

    Duerr, Ann; Wasserheit, Judith N; Corey, Lawrence

    2006-08-15

    A human immunodeficiency virus (HIV) vaccine is the most promising and feasible strategy to prevent the events during acute infection that simultaneously set the course of the epidemic in the community and the course of the disease for the individual. Because safety concerns limit the use of live, attenuated HIV and inactivated HIV, a variety of alternate approaches is being investigated. Traditional antibody-mediated approaches using recombinant HIV envelope proteins have shown no efficacy in 2 phase III trials. Current HIV vaccine trials are focusing primarily on cytotoxic T lymphocyte-mediated products that use viral vectors, either alone or as boosts to DNA plasmids that contain viral genes. The most immunogenic of these products appear to be the recombinant adenovirus vector vaccines, 2 of which are now in advanced clinical development.

  1. Formulation in DDA-MPLA-TDB Liposome Enhances the Immunogenicity and Protective Efficacy of a DNA Vaccine against Mycobacterium tuberculosis Infection

    PubMed Central

    Tian, Maopeng; Zhou, Zijie; Tan, Songwei; Fan, Xionglin; Li, Longmeng; Ullah, Nadeem

    2018-01-01

    Despite the vaccine Mycobacterium bovis Bacillus Calmette–Guérin is used worldwide, tuberculosis (TB) remains the first killer among infectious diseases. An effective vaccine is urgently required. DNA vaccine has shown prophylactic as well as therapeutic effects against TB, while its weak immunogenicity hinders the application. As a strong inducer of Th1-biased immune response, DMT, consisting of dimethyldioctadecylammonium (DDA) and two pattern recognition receptor agonists monophosphoryl lipid A and trehalose 6,6′-dibehenate (TDB), was a newly developed liposomal adjuvant. To elucidate the action mechanism of DMT and improve immunological effects induced by DNA vaccine, a new recombinant eukaryotic expression plasmid pCMFO that secretes the fusion of four multistage antigens (Rv2875, Rv3044, Rv2073c, and Rv0577) of Mycobacterium tuberculosis was constructed. pCMFO/DDA and pCMFO/DMT complexes were then prepared and their physicochemical properties were analyzed. The immunogenicity and protection against M. tuberculosis infection in vaccinated C57BL/6 mice were compared. Formulation of DNA and two agonists into the DDA liposome decreased zeta potential but increased the stability of storage, which resulted in a slower and longer-lasting release of DNA from the DNA–DMT complex than the DNA–DDA liposome. Besides Th1-biased responses, pCMFO/DMT vaccinated mice elicited more significantly CFMO-specific IL2+ TCM cell responses in the spleen and provided an enhanced and persistent protection against M. tuberculosis aerosol infection, compared to pCMFO/DDA and pCMFO groups. Therefore, the adjuvant DMT can release DNA and agonists slowly, which might attribute to the improved protection of DMT adjuvanted vaccines. pCMFO/DMT, a very promising TB vaccine, warrants for further preclinical and clinical trials. PMID:29535714

  2. In vitro pharmacokinetic/pharmacodynamic models in anti-infective drug development: focus on TB

    PubMed Central

    Vaddady, Pavan K; Lee, Richard E; Meibohm, Bernd

    2011-01-01

    For rapid anti-tuberculosis (TB) drug development in vitro pharmacokinetic/pharmacodynamic (PK/PD) models are useful in evaluating the direct interaction between the drug and the bacteria, thereby guiding the selection of candidate compounds and the optimization of their dosing regimens. Utilizing in vivo drug-clearance profiles from animal and/or human studies and simulating them in an in vitro PK/PD model allows the in-depth characterization of antibiotic activity of new and existing antibacterials by generating time–kill data. These data capture the dynamic interplay between mycobacterial growth and changing drug concentration as encountered during prolonged drug therapy. This review focuses on important PK/PD parameters relevant to anti-TB drug development, provides an overview of in vitro PK/PD models used to evaluate the efficacy of agents against mycobacteria and discusses the related mathematical modeling approaches of time–kill data. Overall, it provides an introduction to in vitro PK/PD models and their application as critical tools in evaluating anti-TB drugs. PMID:21359155

  3. Partial reconstitution of the CD4+-T-cell compartment in CD4 gene knockout mice restores responses to tuberculosis DNA vaccines.

    PubMed

    D'Souza, Sushila; Romano, Marta; Korf, Johanna; Wang, Xiao-Ming; Adnet, Pierre-Yves; Huygen, Kris

    2006-05-01

    Reactivation tuberculosis (TB) is a serious problem in immunocompromised individuals, especially those with human immunodeficiency virus (HIV) coinfection. The adaptive immune response mediated by CD4+ and CD8+ T cells is known to confer protection against TB. Hence, vaccines against TB are designed to activate these two components of the immune system. Anti-TB DNA vaccines encoding the immunodominant proteins Ag85A, Ag85B, and PstS-3 from Mycobacterium tuberculosis are ineffective in mice lacking CD4+ T cells (CD4-/- mice). In this study, we demonstrate that reconstitution of the T-cell compartment in CD4-/- mice restores vaccine-specific antibody and gamma interferon (IFN-gamma) responses to these DNA vaccines. The magnitude of the immune responses correlated with the extent of reconstitution of the CD4+-T-cell compartment. Reconstituted mice vaccinated with DNA encoding PstS-3, known to encode a dominant D(b)-restricted CD8+-T-cell epitope, displayed CD8+-T-cell responses not observed in CD4-/- mice. M. tuberculosis challenge in reconstituted mice led to the extravasation of IFN-gamma-producing CD4+ and CD8+ T cells into lungs, the primary site of bacterial replication. Importantly, a reconstitution of 12 to 15% of the CD4+-T-cell compartment resulted in Ag85B plasmid DNA-mediated protection against a challenge M. tuberculosis infection. Our findings provide evidence that anti-TB DNA vaccines could be effective in immunodeficient individuals after CD4+-T-lymphocyte reconstitution, as may occur following antiretroviral therapy in HIV+ patients.

  4. Oral vaccination of guinea pigs with a Mycobacterium bovis bacillus Calmette-Guerin vaccine in a lipid matrix protects against aerosol infection with virulent M. bovis.

    PubMed

    Clark, Simon; Cross, Martin L; Nadian, Allan; Vipond, Julia; Court, Pinar; Williams, Ann; Hewinson, R Glyn; Aldwell, Frank E; Chambers, Mark A

    2008-08-01

    Increased incidence of bovine tuberculosis (TB) in the United Kingdom caused by infection with Mycobacterium bovis is a cause of considerable economic loss to farmers and the government. The Eurasian badger (Meles meles) represents a wildlife source of recurrent M. bovis infections of cattle in the United Kingdom, and its vaccination against TB with M. bovis bacillus Calmette-Guérin (BCG) is an attractive disease control option. Delivery of BCG in oral bait holds the best prospect for vaccinating badgers over a wide geographical area. Using a guinea pig pulmonary challenge model, we evaluated the protective efficacy of candidate badger oral vaccines, based on broth-grown or ball-milled BCG, delivered either as aqueous suspensions or formulated in two lipids with differing fatty acid profiles (one being animal derived and the other being vegetable derived). Protection was determined in terms of increasing body weight after aerosol challenge with virulent M. bovis, reduced dissemination of M. bovis to the spleen, and, in the case of one oral formulation, restricted growth of M. bovis in the lungs. Only oral BCG formulated in lipid gave significant protection. These data point to the potential of the BCG-lipid formulation for further development as a tool for controlling tuberculosis in badgers.

  5. Vaccination Against Dengue: Challenges and Current Developments.

    PubMed

    Guy, Bruno; Lang, Jean; Saville, Melanie; Jackson, Nicholas

    2016-01-01

    Dengue is a growing threat worldwide, and the development of a vaccine is a public health priority. The completion of the active phase of two pivotal efficacy studies conducted in Asia and Latin America by Sanofi Pasteur has constituted an important step. Several other approaches are under development, and whichever technology is used, vaccine developers face several challenges linked to the particular nature and etiology of dengue disease. We start our review by defining questions and potential issues linked to dengue pathology and presenting the main types of vaccine approaches that have explored these questions; some of these candidates are in a late stage of clinical development. In the second part of the review, we focus on the Sanofi Pasteur dengue vaccine candidate, describing the steps from research to phase III efficacy studies. Finally, we discuss what could be the next steps, before and after vaccine introduction, to ensure that the vaccine will provide the best benefit with an acceptable safety profile to the identified target populations.

  6. Vaccines against enteric infections for the developing world.

    PubMed

    Czerkinsky, Cecil; Holmgren, Jan

    2015-06-19

    Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors: -limited knowledge regarding the properties of the gut immune system during early life; -lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines; -lack of correlates/surrogates of mucosal immune protection; and -limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries. There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world's poorest, confer long-term protection and herd immunity, and must be able to contain epidemics. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  7. Developing a Framework for Evaluating Ethical Outcomes of Good Participatory Practices in TB Clinical Drug Trials.

    PubMed

    MacQueen, Kathleen M; Eley, Natalie T; Frick, Mike; Mingote, Laia Ruiz; Chou, Alicia; Seidel, Stephanie S; Hannah, Stacey; Hamilton, Carol

    2016-07-01

    Good Participatory Practice Guidelines for TB Drug Trials (GPP-TB) were issued in 2012, based on similar guidelines for HIV prevention and reflecting growing acceptance of the importance of community engagement and participatory strategies in clinical research. Though the need for such strategies is clear, evaluation of the benefits and burdens are needed. Working with a diverse group of global TB stakeholders including advocates, scientists, and ethicists, we used a Theory of Change approach to develop an evaluation framework for GPP-TB that includes a clearly defined ethical goal, a set of powerful strategies derived from GPP-TB practices for achieving the goal, and outcomes connecting strategies to goal. The framework is a first step in systematically evaluating participatory research in clinical trials. © The Author(s) 2016.

  8. WHO policy development processes for a new vaccine: case study of malaria vaccines.

    PubMed

    Milstien, Julie; Cárdenas, Vicky; Cheyne, James; Brooks, Alan

    2010-06-24

    Recommendations from the World Health Organization (WHO) are crucial to inform developing country decisions to use, or not, a new intervention. This article analysed the WHO policy development process to predict its course for a malaria vaccine. The decision-making processes for one malaria intervention and four vaccines were classified through (1) consultations with staff and expert advisors to WHO's Global Malaria Programme (GMP) and Immunization, Vaccines and Biologicals Department (IVB); (2) analysis of the procedures and recommendations of the major policy-making bodies of these groups; (3) interviews with staff of partnerships working toward new vaccine availability; and (4) review and analyses of evidence informing key policy decisions. WHO policy formulation related to use of intermittent preventive treatment in infancy (IPTi) and the following vaccine interventions: Haemophilus influenzae type b conjugate vaccine (Hib), pneumococcal conjugate vaccine (PCV), rotavirus vaccine (RV), and human papillomavirus vaccine (HPV), five interventions which had relatively recently been through systematic WHO policy development processes as currently constituted, was analysed. Required information was categorized in three areas defined by a recent WHO publication on development of guidelines: safety and efficacy in relevant populations, implications for costs and population health, and localization of data to specific epidemiological situations. Data needs for a malaria vaccine include safety; the demonstration of efficacy in a range of epidemiological settings in the context of other malaria prevention interventions; and information on potential rebound in which disease increases subsequent to the intervention. In addition, a malaria vaccine would require attention to additional factors, such as costs and cost-effectiveness, supply and demand, impact of use on other interventions, and distribution issues. Although policy issues may be more complex for future vaccines

  9. [Rabies vaccines: Current status and prospects for development].

    PubMed

    Starodubova, E S; Preobrazhenskaia, O V; Kuzmenko, Y V; Latanova, A A; Yarygina, E I; Karpov, V L

    2015-01-01

    Rabies is an infectious disease among humans and animals that remains incurable, despite its longstanding research history. The only way to prevent the disease is prompt treatment, including vaccination as an obligatory component and administration of antirabies immunoglobulin as a supplement. Since the first antirabies vaccination performed in the 19th century, a large number of different rabies vaccines have been developed. Progress in molecular biology and biotechnology enabled the development of effective and safe technologies of vaccine production. Currently, new-generation vaccines are being developed based on recombinant rabies virus strains or on the production of an individual recombinant rabies antigen-glycoprotein (G protein), either as a component of nonpathogenic viruses, or in plants, or in the form of DNA vaccines. In this review, the main modern trends in the development of rabies vaccines have been discussed.

  10. Update on progress in HIV vaccine development.

    PubMed

    Watkins, David I

    2012-01-01

    The 19th Conference on Retroviruses and Opportunistic Infections heralded the arrival of a new crop of potent, broadly neutralizing antibodies against HIV. This advance has given the entire vaccine field enormous hope that it will be possible one day to develop an antibody-based vaccine for HIV. However, substantial obstacles still exist in the induction of these antibodies by vaccination, given the enormous number of somatic mutations needed to develop these highly efficient antibodies. It is likely that follicular helper T cells will be involved in the development of these antibodies, and this will be a key area of interest in the future. Cellular immune responses will also be an important part of any vaccine regimen. Evidence showed that protection provided by an attenuated vaccine correlated with the frequency of vaccine-induced helper cells and killer cells, underlining the importance of these key immune cells. An alternative approach to the development of potent neutralizing antibodies was presented as part of an update on the Thai Phase III Vaccine Trial RV144. Data were shown suggesting that binding antibodies may play a role in protection from HIV infection.

  11. Developments in rabies vaccines.

    PubMed

    Hicks, D J; Fooks, A R; Johnson, N

    2012-09-01

    The development of vaccines that prevent rabies has a long and distinguished history, with the earliest preceding modern understanding of viruses and the mechanisms of immune protection against disease. The correct application of inactivated tissue culture-derived vaccines is highly effective at preventing the development of rabies, and very few failures are recorded. Furthermore, oral and parenteral vaccination is possible for wildlife, companion animals and livestock, again using inactivated tissue culture-derived virus. However, rabies remains endemic in many regions of the world and causes thousands of human deaths annually. There also remain no means of prophylaxis for rabies once the virus enters the central nervous system (CNS). One reason for this is the poor immune response within the CNS to infection with rabies virus (RABV). New approaches to vaccination using modified rabies viruses that express components of the innate immune system are being applied to this problem. Preliminary reports suggest that direct inoculation of such viruses could trigger an effective anti-viral response and prevent a fatal outcome from RABV infection. © 2012 Crown copyright. Clinical and Experimental Immunology © 2012 British Society for Immunology.

  12. Conjugation of TbPO4·H2O-Based Nanowires with Immunoglobulin G for Bioimaging

    NASA Astrophysics Data System (ADS)

    Huong, Nguyen Thanh; Lien, Pham Thi; Hung, Nguyen Manh; Van, Nguyen Duc; Thuy, Tran Thi; Binh, Nguyen Thanh; Minh, Le Quoc

    2016-05-01

    The surface modification, functionalization, and conjugation of undoped and 11 at.% Eu3+-doped TbPO4 ·H2O nanowires by using silica, a thyocyanate functional group, and immunoglobulin G, respectively, are described in this paper. For the core layer of obtained conjugated nanowires, the undoped TbPO4 ·H2O exhibited characteristic photoluminescent green emission corresponding to 5 D 4 → 7 F J transitions ( J = 6, 5, 4, 3) while the incorporation of Eu3+ into TbPO4 ·H2O lattice was evidenced by Starks splitting transitions at 590, 615, 693 nm of Eu3+ ions for the case of 11 at.% Eu3+-doped TbPO4 ·H2O. The results also indicated that both immunoglobulin G-conjugated undoped and Eu3+-doped TbPO4 ·H2O nanowires can be used in the fluorescent immune analysis as a biomedical label maker to identify measles viruses in vaccine testing.

  13. Developing live vaccines against Yersinia pestis

    PubMed Central

    Sun, Wei; Roland, Kenneth L.; Curtiss, Roy

    2014-01-01

    Three great plague pandemics caused by the gram-negative bacterium Yersinia pestis have killed nearly 200 million people and it has been linked to biowarfare in the past. Plague is endemic in many parts of the world. In addition, the risk of plague as a bioweapon has prompted increased research to develop plague vaccines against this disease. Injectable subunit vaccines are being developed in the United States and United Kingdom. However, the live attenuated Y. pestis-EV NIIEG strain has been used as a vaccine for more than 70 years in the former Soviet Union and in some parts of Asia and provides a high degree of efficacy against plague. This vaccine has not gained general acceptance because of safety concerns. In recent years, modern molecular biological techniques have been applied to Y. pestis to construct strains with specific defined mutations designed to create safe, immunogenic vaccines with potential for use in humans and as bait vaccines to reduce the load of Y. pestis in the environment. In addition, a number of live, vectored vaccines have been reported using attenuated viral vectors or attenuated Salmonella strains to deliver plague antigens. Here we summarize the progress of live attenuated vaccines against plague. PMID:21918302

  14. Recent developments in leishmaniasis vaccine delivery systems.

    PubMed

    Bhowmick, Sudipta; Ali, Nahid

    2008-07-01

    The observation that recovery from infection with Leishmania confers immunity to reinfection suggests that control of leishmaniasis by vaccination may be possible. New generation vaccines, particularly those based on recombinant proteins and DNA, are found to be less immunogenic. There is an urgent need for the development of new and improved vaccine adjuvants. Based on their principal mechanisms of action, adjuvants can be broadly separated into two classes: immunostimulatory adjuvants and vaccine delivery systems. Vaccine delivery systems can carry both antigen and adjuvant for effective delivery to the antigen-presenting cells (APCs). In this article, we review the adjuvants, the delivery systems and their combinations used in the search of an effective vaccine against leishmaniasis. Based on current knowledge, cationic liposomes appear to have better prospects as effective delivery systems for developing a vaccine for leishmaniasis.

  15. Prevalence of latent TB infection and TB disease among adolescents in high TB burden countries in Africa: a systematic review protocol.

    PubMed

    Bunyasi, Erick Wekesa; Schmidt, Bey-Marrie; Abdullahi, Leila Hussein; Mulenga, Humphrey; Tameris, Michele; Luabeya, Angelique; Shenje, Justin; Scriba, Thomas; Geldenhuys, Hennie; Wood, Robin; Hatherill, Mark

    2017-03-10

    Almost a third of the world population has latent tuberculosis (TB) infection (LTBI), ∼10 million of whom develop TB disease annually, despite existence of effective, but lengthy, preventive and curative drug regimens. Although adolescents appear to have a very high force of LTBI, their reported incidence of TB disease is less than that of their corresponding general population. The few available studies on adolescent TB infection and disease prevalence are not sufficient to address the apparent discordance between rates of infection and disease in high TB burden countries in Africa. Therefore, we aim to perform a systematic review to examine the relationship between adolescent LTBI and TB disease, benchmarked against national TB disease burden data. A comprehensive literature search will be performed for cross-sectional studies and screening data in cohort studies to determine the prevalence of LTBI and TB disease among adolescents in high TB burden countries in Africa in the following databases: PubMed , Scopus , Cochrane library , Web of Science , Africa Wide , CINAHL and the Africa Index Medicus . This will be supplemented by a search of reference lists of selected articles for potentially relevant articles. We will restrict our search to articles published in the English language between 1990 and 2016 among adolescents in order to obtain estimates reflective of the mature HIV epidemic in most high TB burden countries in Africa that occurred over this critical period. Primary end points are: prevalence of LTBI and TB disease. We will use the random-effects or fixed-effects modelling for our meta-analysis based on heterogeneity estimates. No ethics approval is required given that this is a systematic review. Findings will be disseminated in a peer-reviewed journal in line with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). CRD42015023495. Published by the BMJ Publishing Group Limited. For permission to use (where not already

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

    PubMed Central

    2011-01-01

    Background Bacille Calmette-Guerin (BCG) is currently the only available vaccine against tuberculosis (TB) and comprises a heterogeneous family of sub-strains with genotypic and phenotypic differences. The World Health Organization (WHO) affirms that the characterization of BCG sub-strains, both on genomic and proteomic levels, is crucial for a better comprehension of the vaccine. In addition, these studies can contribute in the development of a more efficient vaccine against TB. Here, we combine two-dimensional electrophoresis (2DE) and mass spectrometry to analyse the proteomic profile of culture filtrate proteins (CFPs) from M. bovis BCG Moreau, the Brazilian vaccine strain, comparing it to that of BCG Pasteur. CFPs are considered of great importance given their dominant immunogenicity and role in pathogenesis, being available for interaction with host cells since early infection. Results The 2DE proteomic map of M. bovis BCG Moreau CFPs in the pH range 3 - 8 allowed the identification of 158 spots corresponding to 101 different proteins, identified by MS/MS. Comparison to BCG Pasteur highlights the great similarity between these BCG strains. However, quantitative analysis shows a higher expression of immunogenic proteins such as Rv1860 (BCG1896, Apa), Rv1926c (BCG1965c, Mpb63) and Rv1886c (BCG1923c, Ag85B) in BCG Moreau when compared to BCG Pasteur, while some heat shock proteins, such as Rv0440 (BCG0479, GroEL2) and Rv0350 (BCG0389, DnaK), show the opposite pattern. Conclusions Here we report the detailed 2DE profile of CFPs from M. bovis BCG Moreau and its comparison to BCG Pasteur, identifying differences that may provide relevant information on vaccine efficacy. These findings contribute to the detailed characterization of the Brazilian vaccine strain against TB, revealing aspects that may lead to a better understanding of the factors leading to BCG's variable protective efficacy against TB. PMID:21507239

  17. Anti-Lyme Subunit Vaccines: Design and Development of Peptide-Based Vaccine Candidates.

    PubMed

    Small, Christina M; Mwangi, Waithaka; Esteve-Gassent, Maria D

    2016-01-01

    Vaccinology today has been presented with several avenues to improve protection against infectious disease. The recent employment of the reverse vaccinology technique has changed the face of vaccine development against many pathogens, including Borrelia burgdorferi, the causative agent of Lyme disease. Using this technique, genomics and in silico analyses come together to identify potentially antigenic epitopes in a high-throughput fashion. The forward methodology of vaccine development was used previously to generate the only licensed human vaccine for Lyme disease, which is no longer on the market. Using reverse vaccinology to identify new antigens and isolate specific epitopes to protect against B. burgdorferi, subunit vaccines will be generated that lack reactogenic and nonspecific epitopes, yielding more effective vaccine candidates. Additionally, novel epitopes are being utilized and are presently in the commercialization pipeline both for B. burgdorferi and other spirochaetal pathogens. The versatility and methodology of the subunit protein vaccine are described as it pertains to Lyme disease from conception to performance evaluation.

  18. Bacillus Calmette-Guérin vaccination reduces the severity and progression of tuberculosis in badgers

    PubMed Central

    Chambers, Mark A.; Rogers, Fiona; Delahay, Richard J.; Lesellier, Sandrine; Ashford, Roland; Dalley, Deanna; Gowtage, Sonya; Davé, Dipesh; Palmer, Si; Brewer, Jacky; Crawshaw, Timothy; Clifton-Hadley, Richard; Carter, Steve; Cheeseman, Chris; Hanks, Chris; Murray, Alistair; Palphramand, Kate; Pietravalle, Stéphane; Smith, Graham C.; Tomlinson, Alexandra; Walker, Neil J.; Wilson, Gavin J.; Corner, Leigh A. L.; Rushton, Stephen P.; Shirley, Mark D. F.; Gettinby, George; McDonald, Robbie A.; Hewinson, R. Glyn

    2011-01-01

    Control of bovine tuberculosis (TB) in cattle has proven particularly challenging where reservoirs of infection exist in wildlife populations. In Britain and Ireland, control is hampered by a reservoir of infection in Eurasian badgers (Meles meles). Badger culling has positive and negative effects on bovine TB in cattle and is difficult, costly and controversial. Here we show that Bacillus Calmette-Guérin (BCG) vaccination of captive badgers reduced the progression, severity and excretion of Mycobacterium bovis infection after experimental challenge. In a clinical field study, BCG vaccination of free-living badgers reduced the incidence of positive serological test results by 73.8 per cent. In common with other species, BCG did not appear to prevent infection of badgers subjected to experimental challenge, but did significantly reduce the overall disease burden. BCG vaccination of badgers could comprise an important component of a comprehensive programme of measures to control bovine TB in cattle. PMID:21123260

  19. Screening contacts of patients with extrapulmonary TB for latent TB infection.

    PubMed

    Humphreys, Anna; Abbara, Aula; Williams, Sion; John, Laurence; Corrah, Tumena; McGregor, Alastair; Davidson, Robert N

    2018-03-01

    2016 TB National Institute for Health and Care Excellence (NICE) guidelines imply that contacts of extrapulmonary TB do not require screening for latent TB infection. At our high TB prevalence site, we identified 189 active cases of TB for whom there were 698 close contacts. 29.1% of the contacts of pulmonary TB and 10.7% of the contacts of extrapulmonary TB had active or latent TB infection. This supports screening contacts of extrapulmonary TB at our site and presents a way to access high-risk individuals. We propose to continue to screen the contacts of our patients with extrapulmonary TB and recommend other TB units audit their local results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. Immunological and physical evaluation of the multistage tuberculosis subunit vaccine candidate H56/CAF01 formulated as a spray-dried powder.

    PubMed

    Thakur, Aneesh; Ingvarsson, Pall Thor; Schmidt, Signe Tandrup; Rose, Fabrice; Andersen, Peter; Christensen, Dennis; Foged, Camilla

    2018-05-31

    support our ongoing efforts to develop a thermostable, dry powder-based TB vaccine. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Improving the malaria transmission-blocking activity of a Plasmodium falciparum 48/45 based vaccine antigen by SpyTag/SpyCatcher mediated virus-like display.

    PubMed

    Singh, Susheel K; Thrane, Susan; Janitzek, Christoph M; Nielsen, Morten A; Theander, Thor G; Theisen, Michael; Salanti, Ali; Sander, Adam F

    2017-06-27

    Malaria is a devastating disease caused by Plasmodium parasites, resulting in almost 0.5 million deaths per year. The Pfs48/45 protein exposed on the P. falciparum sexual stages is one of the most advanced antigen candidates for a transmission-blocking (TB) vaccine in the clinical pipeline. However, it remains essential to identify an optimal vaccine formulation that can facilitate induction of a long-lasting TB anti-Pfs48/45 response. Here we report on the development and evaluation of two Pfs48/45-based virus-like particle (VLP) vaccines generated using the AP205 SpyTag/Catcher VLP system. Two different recombinant proteins (SpyCatcher-R0.6C and SpyCatcher-6C), comprising the Pfs48/45-6C region, were covalently attached to the surface of Spy-tagged Acinetobacter phage AP205 VLPs. Resulting Pfs48/45-VLP complexes appeared as non-aggregated particles of ∼30nm, each displaying an average of 216 (R0.6C) or 291 (6C) copies of the antigens. Both R0.6C and 6C VLP conjugates were strongly reactive with a monoclonal antibody (mAb45.1) targeting a conformational TB Pfs48/45 epitope, suggesting that the TB epitope is accessible for immune recognition on the particles. To select the most suitable vaccine formulation for downstream clinical studies the two VLP vaccines were tested in CD1 mice using different adjuvant formulations. The study demonstrates that VLP-display of R0.6C and 6C significantly increases antigen immunogenicity when using Montanide ISA 720 VG as extrinsic adjuvant. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The development of global vaccine stockpiles.

    PubMed

    Yen, Catherine; Hyde, Terri B; Costa, Alejandro J; Fernandez, Katya; Tam, John S; Hugonnet, Stéphane; Huvos, Anne M; Duclos, Philippe; Dietz, Vance J; Burkholder, Brenton T

    2015-03-01

    Global vaccine stockpiles, in which vaccines are reserved for use when needed for emergencies or supply shortages, have effectively provided countries with the capacity for rapid response to emergency situations, such as outbreaks of yellow fever and meningococcal meningitis. The high cost and insufficient supply of many vaccines, including oral cholera vaccine and pandemic influenza vaccine, have prompted discussion on expansion of the use of vaccine stockpiles to address a wider range of emerging and re-emerging diseases. However, the decision to establish and maintain a vaccine stockpile is complex and must take account of disease and vaccine characteristics, stockpile management, funding, and ethical concerns, such as equity. Past experience with global vaccine stockpiles provide valuable information about the processes for their establishment and maintenance. In this Review we explored existing literature and stockpile data to discuss the lessons learned and to inform the development of future vaccine stockpiles. Copyright © 2015 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd. All rights reserved.

  3. Status of vaccine research and development of vaccines for leishmaniasis.

    PubMed

    Gillespie, Portia M; Beaumier, Coreen M; Strych, Ulrich; Hayward, Tara; Hotez, Peter J; Bottazzi, Maria Elena

    2016-06-03

    A number of leishmaniasis vaccine candidates are at various stages of pre-clinical and clinical development. Leishmaniasis is a vector-borne neglected tropical disease (NTD) caused by a protozoan parasite of the genus Leishmania and transmitted to humans by the bite of a sand fly. Visceral leishmaniasis (VL, kala-azar) is a high mortality NTD found mostly in South Asia and East Africa, while cutaneous leishmaniasis (CL) is a disfiguring NTD highly endemic in the Middle East, Central Asia, North Africa, and the Americas. Estimates attribute 50,000 annual deaths and 3.3 million disability-adjusted life years to leishmaniasis. There are only a few approved drug treatments, no prophylactic drug and no vaccine. Ideally, an effective vaccine against leishmaniasis will elicit long-lasting immunity and protect broadly against VL and CL. Vaccines such as Leish-F1, F2 and F3, developed at IDRI and designed based on selected Leishmania antigen epitopes, have been in clinical trials. Other groups, including the Sabin Vaccine Institute in collaboration with the National Institutes of Health are investigating recombinant Leishmania antigens in combination with selected sand fly salivary gland antigens in order to augment host immunity. To date, both VL and CL vaccines have been shown to be cost-effective in economic modeling studies. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  4. Multidrug-Resistant TB

    PubMed Central

    Cox, Helen; Coomans, Fons

    2016-01-01

    Abstract The right to enjoy the benefits of scientific progress (REBSP) is a little-known but potentially valuable right that can contribute to rights-based approaches to addressing multidrug-resistant TB (MDR-TB). We argue that better understanding of the REBSP may help to advance legal and civil society action for health rights. While the REBSP does not provide an individual entitlement to have a new drug developed for MDR-TB, it sets up entitlements to expect a state to establish a legislative and policy framework aimed at developing scientific capacity to address the most important health issues and at disseminating the outcomes of scientific research. By making scientific findings available and accessible, people can be enabled to claim the use of science for social benefits. Inasmuch as the market fails to address neglected diseases such as MDR-TB, the REBSP provides a potential counterbalance to frame a positive obligation on states to both marshal their own resources and to coordinate the actions of multiple other actors towards this goal, including non-state actors. While the latter do not hold the same level of accountability as states, the REBSP can still enable the recognition of obligations at a level of “soft law” responsibilities. PMID:27780997

  5. TB-IRIS and remodelling of the T cell compartment in highly immunosuppressed HIV+ patients with TB: the CAPRI T (ANRS-12614) study

    PubMed Central

    Haridas, V.; Pean, P.; Jasenosky, L.D.; Madec, Y.; Laureillard, D.; Sok, T.; Sath, S.; Borand, L.; Marcy, O.; Chan, S.; Tsitsikov, E.; Delfraissy, J.-F.; Blanc, F.-X.; Goldfeld, A.E.

    2015-01-01

    Objective To investigate the impact of tuberculosis (TB)-associated immune reconstitution syndrome (IRIS) upon immunological recovery and the T cell compartment after initiation of TB and antiretroviral therapy (ART). Design and methods We prospectively evaluated T cell immunophenotypes by flow cytometry and cytokines by Luminex assays in a subset (n=154) of highly immunosuppressed HIV+ patients with TB from the CAMELIA randomized clinical trial. We compared findings from patients who developed TB-IRIS to findings from patients who did not develop TB-IRIS. Data were evaluated with mixed effect linear regression, Kaplan-Meier estimates, and Wilcoxon rank sum tests, and q-values were calculated to control for multiple comparisons. Results Development of TB-IRIS was associated with significantly greater pre-ART frequencies of HLA-DR+CD45RO+CD4+, CCR5+CD4+, OX40+CD4+, and Fas+ effector memory (EM) CD8+ T cells, and significantly elevated levels of plasma IL-6, IL-1β, IL-8, and IL-10 and viral load. Post-ART initiation, EM CD4+ and Fas+ EM CD4+ T cell frequencies significantly expanded, and central memory (CM) CD4+ T cell frequencies significantly contracted in patients who experienced TB-IRIS. By week 34 post-TB treatment initiation, EM/CM CD4+ T cell ratios were markedly higher in TB-IRIS versus non-TB-IRIS patients. Conclusions A distinct pattern of pre-ART T cell and cytokine markers appear to poise the immune response to develop TB-IRIS. Experience of TB-IRIS is then associated with long-term remodeling of the CD4+ T cell memory compartment towards an EM-dominated phenotype. We speculate that these pre- and post-ART TB-IRIS-associated immune parameters may contribute to superior immune control of TB/HIV co-infection and better clinical outcome. PMID:25486415

  6. Identifying vaccine targets for anti-leishmanial vaccine development

    PubMed Central

    Sundar, Shyam; Singh, Bhawana

    2014-01-01

    Leishmaniasis is a neglected tropical disease spread by an arthropod vector. It remains a significant health problem with an incidence of 0.2–0.4 million VL and 0.7–1.2 million CL cases each year. There are limitations associated with the current therapeutic regimens for leishmaniasis and the fact that after recovery from infection the host becomes immune to subsequent infection therefore, these factors forces the feasibility of a vaccine for leishmaniasis. Publication of the genome sequence of Leishmania has paved a new way to understand the pathogenesis and host immunological status therefore providing a deep insight in the field of vaccine research. This review is an effort to study the antigenic targets in Leishmania to develop anti-leishmanial vaccine. PMID:24606556

  7. Global Vaccine and Immunization Research Forum: Opportunities and challenges in vaccine discovery, development, and delivery.

    PubMed

    Ford, Andrew Q; Touchette, Nancy; Hall, B Fenton; Hwang, Angela; Hombach, Joachim

    2016-03-18

    The World Health Organization, the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, and the Bill & Melinda Gates Foundation convened the first Global Vaccine and Immunization Research Forum (GVIRF) in March 2014. This first GVIRF aimed to track recent progress of the Global Vaccine Action Plan research and development agenda, identify opportunities and challenges, promote partnerships in vaccine research, and facilitate the inclusion of all stakeholders in vaccine research and development. Leading scientists, vaccine developers, and public health officials from around the world discussed scientific and technical challenges in vaccine development, research to improve the impact of immunization, and regulatory issues. This report summarizes the discussions and conclusions from the forum participants. Copyright © 2016. Published by Elsevier Ltd.. All rights reserved.

  8. Development and trial of vaccines against Brucella.

    PubMed

    Lalsiamthara, Jonathan; Lee, John Hwa

    2017-08-31

    The search for ideal brucellosis vaccines remains active today. Currently, no licensed human or canine anti-brucellosis vaccines are available. In bovines, the most successful vaccine (S19) is only used in calves, as adult vaccination results in orchitis in male, prolonged infection, and possible abortion complications in pregnant female cattle. Another widely deployed vaccine (RB51) has a low protective efficacy. An ideal vaccine should exhibit a safe profile as well as enhance protective efficacy. However, currently available vaccines exhibit one or more major drawbacks. Smooth live attenuated vaccines suffer shortcomings such as residual virulence and serodiagnostic interference. Inactivated vaccines, in general, confer relatively low levels of protection. Recent developments to improve brucellosis vaccines include generation of knockout mutants by targeting genes involved in metabolism, virulence, and the lipopolysaccharide synthesis pathway, as well as generation of DNA vaccines, mucosal vaccines, and live vectored vaccines, have all produced varying degrees of success. Herein, we briefly review the bacteriology, pathogenesis, immunological implications, candidate vaccines, vaccinations, and models related to Brucella .

  9. Development and trial of vaccines against Brucella

    PubMed Central

    Lalsiamthara, Jonathan

    2017-01-01

    The search for ideal brucellosis vaccines remains active today. Currently, no licensed human or canine anti-brucellosis vaccines are available. In bovines, the most successful vaccine (S19) is only used in calves, as adult vaccination results in orchitis in male, prolonged infection, and possible abortion complications in pregnant female cattle. Another widely deployed vaccine (RB51) has a low protective efficacy. An ideal vaccine should exhibit a safe profile as well as enhance protective efficacy. However, currently available vaccines exhibit one or more major drawbacks. Smooth live attenuated vaccines suffer shortcomings such as residual virulence and serodiagnostic interference. Inactivated vaccines, in general, confer relatively low levels of protection. Recent developments to improve brucellosis vaccines include generation of knockout mutants by targeting genes involved in metabolism, virulence, and the lipopolysaccharide synthesis pathway, as well as generation of DNA vaccines, mucosal vaccines, and live vectored vaccines, have all produced varying degrees of success. Herein, we briefly review the bacteriology, pathogenesis, immunological implications, candidate vaccines, vaccinations, and models related to Brucella. PMID:28859268

  10. On the impact of masking and blocking hypotheses for measuring the efficacy of new tuberculosis vaccines.

    PubMed

    Arregui, Sergio; Sanz, Joaquín; Marinova, Dessislava; Martín, Carlos; Moreno, Yamir

    2016-01-01

    Over the past 60 years, the Mycobacterium bovis bacille Calmette-Guérin (BCG) has been used worldwide to prevent tuberculosis (TB). However, BCG has shown a very variable efficacy in different trials, offering a wide range of protection in adults against pulmonary TB. One of the most accepted hypotheses to explain these inconsistencies points to the existence of a pre-existing immune response to antigens that are common to environmental sources of mycobacterial antigens and Mycobacterium tuberculosis. Specifically, two different mechanisms have been hypothesized to explain this phenomenon: the masking and the blocking effects. According to masking hypothesis, previous sensitization confers some level of protection against TB that masks vaccine's effects. In turn, the blocking hypothesis postulates that previous immune response prevents vaccine taking of a new TB vaccine. In this work we introduce a series of models to discriminate between masking and blocking mechanisms and address their relative likelihood. We apply our methodology to the data reported by BCG-REVAC clinical trials, which were specifically designed for studying BCG efficacy variability. Our results yield estimates that are consistent with high levels of blocking (41% in Manaus -95% CI [14-68]- and 96% in Salvador -95% CI [52-100]-). Moreover, we also show that masking does not play any relevant role in modifying vaccine's efficacy either alone or in addition to blocking. The quantification of these effects around a plausible model constitutes a relevant step towards impact evaluation of novel anti-tuberculosis vaccines, which are susceptible of being affected by similar effects, especially if applied on individuals previously exposed to mycobacterial antigens.

  11. Low Cost Tuberculosis Vaccine Antigens in Capsules: Expression in Chloroplasts, Bio-Encapsulation, Stability and Functional Evaluation In Vitro

    PubMed Central

    Yang, Xiangdong; Lloyd, Bethany; Daniell, Henry

    2013-01-01

    Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the leading fatal infectious diseases. The development of TB vaccines has been recognized as a major public health priority by the World Health Organization. In this study, three candidate antigens, ESAT-6 (6kDa early secretory antigenic target) and Mtb72F (a fusion polyprotein from two TB antigens, Mtb32 and Mtb39) fused with cholera toxin B-subunit (CTB) and LipY (a cell wall protein) were expressed in tobacco and/or lettuce chloroplasts to facilitate bioencapsulation/oral delivery. Site-specific transgene integration into the chloroplast genome was confirmed by Southern blot analysis. In transplastomic leaves, CTB fusion proteins existed in soluble monomeric or multimeric forms of expected sizes and their expression levels varied depending upon the developmental stage and time of leaf harvest, with the highest-level of accumulation in mature leaves harvested at 6PM. The CTB-ESAT6 and CTB-Mtb72F expression levels reached up to 7.5% and 1.2% of total soluble protein respectively in mature tobacco leaves. Transplastomic CTB-ESAT6 lettuce plants accumulated up to 0.75% of total leaf protein. Western blot analysis of lyophilized lettuce leaves stored at room temperature for up to six months showed that the CTB-ESAT6 fusion protein was stable and preserved proper folding, disulfide bonds and assembly into pentamers for prolonged periods. Also, antigen concentration per gram of leaf tissue was increased 22 fold after lyophilization. Hemolysis assay with purified CTB-ESAT6 protein showed partial hemolysis of red blood cells and confirmed functionality of the ESAT-6 antigen. GM1-binding assay demonstrated that the CTB-ESAT6 fusion protein formed pentamers to bind with the GM1-ganglioside receptor. The expression of functional Mycobacterium tuberculosis antigens in transplastomic plants should facilitate development of a cost-effective and orally deliverable TB booster vaccine with potential for long

  12. Current status of Zika vaccine development: Zika vaccines advance into clinical evaluation.

    PubMed

    Barrett, Alan D T

    2018-01-01

    Zika virus (ZIKV), a mosquito-borne flavivirus, was first identified in the 1940s in Uganda in Africa and emerged in the Americas in Brazil in May 2015. In the 30 months since ZIKV emerged as a major public health problem, spectacular progress has been made with vaccine development cumulating with the publication of three reports of phase 1 clinical trials in the 4th quarter of 2017. Clinical trials involving candidate DNA and purified inactivated virus vaccines showed all were safe and well-tolerated in the small number of volunteers and all induced neutralizing antibodies, although these varied by vaccine candidate and dosing regimen. These results suggest that a Zika vaccine can be developed and that phase 2 clinical trials are warranted. However, it is difficult to compare the results from the different phase 1 studies or with neutralizing antibodies induced by licensed flavivirus vaccines (Japanese encephalitis, tick-borne encephalitis, and yellow fever) as neutralizing antibody assays vary and, unfortunately, there are no standards for Zika virus neutralizing antibodies. In addition to clinical studies, substantial progress continues to be made in nonclinical development, particularly in terms of the ability of candidate vaccines to protect reproductive tissues, and the potential use of monoclonal antibodies for passive prophylaxis.

  13. Immune TB Antibody Phage Display Library as a Tool To Study B Cell Immunity in TB Infections.

    PubMed

    Hamidon, Nurul Hamizah; Suraiya, Siti; Sarmiento, Maria E; Acosta, Armando; Norazmi, Mohd Nor; Lim, Theam Soon

    2018-03-01

    B cells and in particular antibodies has always played second fiddle to cellular immunity in regard to tuberculosis (TB). However, recent studies has helped position humoral immunity especially antibodies back into the foray in relation to TB immunity. Therefore, the ability to correlate the natural antibody responses of infected individuals toward TB antigens would help strengthen this concept. Phage display is an intriguing approach that can be utilized to study antibody-mediated responses against a particular infection via harvesting the B cell repertoire from infected individuals. The development of disease-specific antibody libraries or immune libraries is useful to better understand antibody-mediated immune responses against specific disease antigens. This study describes the generation of an immune single-chain variable fragment (scFv) library derived from TB-infected individuals. The immune library with an estimated diversity of 10 9 independent clones was then applied for the identification of monoclonal antibodies against Mycobacterium tuberculosis α-crystalline as a model antigen. Biopanning of the library isolated three monoclonal antibodies with unique gene usage. This strengthens the role of antibodies in TB immunity in addition to the role played by cellular immunity. The developed library can be applied against other TB antigens and aid antibody-derived TB immunity studies in the future.

  14. Epidemiological determinants of successful vaccine development.

    PubMed

    Nishiura, Hiroshi; Mizumoto, Kenji

    2013-01-01

    Epidemiological determinants of successful vaccine development were explored using measurable biological variables including antigenic stability and requirement of T-cell immunity. Employing a logistic regression model, we demonstrate that a high affinity with blood and immune cells and pathogen interactions (e.g. interference) would be the risk factors of failure for vaccine development.

  15. Vaccine procurement and self-sufficiency in developing countries.

    PubMed

    Woodle, D

    2000-06-01

    This paper discusses the movement toward self-sufficiency in vaccine supply in developing countries (and countries in transition to new economic and political systems) and explains special supply concerns about vaccine as a product class. It traces some history of donor support and programmes aimed at self-financing, then continues with a discussion about self-sufficiency in terms of institutional capacity building. A number of deficiencies commonly found in vaccine procurement and supply in low- and middle-income countries are characterized, and institutional strengthening with procurement technical assistance is described. The paper also provides information about a vaccine procurement manual being developed by the United States Agency for International Development (USAID) and the World Health Organization (WHO) for use in this environment. Two brief case studies are included to illustrate the spectrum of existing capabilities and different approaches to technical assistance aimed at developing or improving vaccine procurement capability. In conclusion, the paper discusses the special nature of vaccine and issues surrounding potential integration and decentralization of vaccine supply systems as part of health sector reform.

  16. Memory T cells and vaccines.

    PubMed

    Esser, Mark T; Marchese, Rocio D; Kierstead, Lisa S; Tussey, Lynda G; Wang, Fubao; Chirmule, Narendra; Washabaugh, Michael W

    2003-01-17

    T lymphocytes play a central role in the generation of a protective immune response in many microbial infections. After immunization, dendritic cells take up microbial antigens and traffic to draining lymph nodes where they present processed antigens to naïve T cells. These naïve T cells are stimulated to proliferate and differentiate into effector and memory T cells. Activated, effector and memory T cells provide B cell help in the lymph nodes and traffic to sites of infection where they secrete anti-microbial cytokines and kill infected cells. At least two types of memory cells have been defined in humans based on their functional and migratory properties. T central-memory (T(CM)) cells are found predominantly in lymphoid organs and can not be immediately activated, whereas T effector-memory (T(EM)) cells are found predominantly in peripheral tissue and sites of inflammation and exhibit rapid effector function. Most currently licensed vaccines induce antibody responses capable of mediating long-term protection against lytic viruses such as influenza and small pox. In contrast, vaccines against chronic pathogens that require cell-mediated immune responses to control, such as malaria, Mycobacterium tuberculosis (TB), human immunodeficiency virus (HIV) and hepatitis C virus (HCV), are currently not available or are ineffective. Understanding the mechanisms by which long-lived cellular immune responses are generated following vaccination should facilitate the development of safe and effective vaccines against these emerging diseases. Here, we review the current literature with respect to memory T cells and their implications to vaccine development.

  17. Vaccine development against Neisseria meningitidis

    PubMed Central

    Vogel, Ulrich; Claus, Heike

    2011-01-01

    Summary Meningococcal disease is communicable by close contact or droplet aerosols. Striking features are high case fatality rates and peak incidences of invasive disease in infants, toddlers and adolescents. Vaccine development is hampered by bacterial immune evasion strategies including molecular mimicry. As for Haemophilus influenzae and Streptococcus pneumoniae, no vaccine has therefore been developed that targets all serogroups of Neisseria meningitidis. Polysaccharide vaccines available both in protein conjugated and non‐conjugated form, have been introduced against capsular serogroups A, C, W‐135 and Y, but are ineffective against serogroup B meningococci, which cause a significant burden of disease in many parts of the world. Detoxified outer membrane vesicles are used since decades to elicit protection against epidemic serogroup B disease. Genome mining and biochemical approaches have provided astounding progress recently in the identification of immunogenic, yet reasonably conserved outer membrane proteins. As subcapsular proteins nevertheless are unlikely to immunize against all serogroup B variants, thorough investigation by surrogate assays and molecular epidemiology approaches are needed prior to introduction and post‐licensure of protein vaccines. Research currently addresses the analysis of life vaccines, meningococcus B polysaccharide modifications and mimotopes, as well as the use of N. lactamicaouter membrane vesicles. PMID:21255369

  18. Interleukin-1 receptor antagonist, a biomarker of response to anti-TB treatment in HIV/TB co-infected patients.

    PubMed

    Nouhin, Janin; Pean, Polidy; Madec, Yoann; Chevalier, Mathieu F; Didier, Celine; Borand, Laurence; Blanc, François-Xavier; Scott-Algara, Daniel; Laureillard, Didier; Weiss, Laurence

    2017-05-01

    Despite the high frequency of tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) in human immunodeficiency virus (HIV)/TB co-infected patients, no diagnostic test is available. Here, we investigated whether monocyte/macrophage activation markers can predict TB-IRIS occurrence and if they are modulated by anti-TB treatment. Frozen plasma was obtained from 127 HIV/TB co-infected adults naïve for antiretroviral therapy, enrolled in the CAMELIA trial, 36 of whom developed TB-IRIS. Concentrations of IL-1Ra, sCD14, and sCD163 were measured at anti-TB treatment onset (baseline), after 8 weeks of anti-TB treatment and at TB-IRIS time. At baseline, IL-1Ra and sCD14 concentrations were similar in TB-IRIS and non-IRIS patients. sCD163 concentrations, although significantly higher in TB-IRIS patients, did not remain associated with TB-IRIS occurrence in multivariate analysis. At the time of TB-IRIS, patients displayed higher concentrations of IL-1Ra (p = 0.002) and sCD14 (p < 0.001). The most striking result was the significant decrease in IL-1Ra after 8 weeks of anti-TB treatment (median reduction: -63% (p < 0.0001)). None of the biomarkers tested was associated with TB-IRIS occurrence. However, repeated measurement of IL-1Ra could help for the diagnosis of TB-IRIS. The substantial reduction of IL-1Ra under treatment suggests that IL-1Ra could be a surrogate biomarker of anti-TB treatment response in HIV-infected patients. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  19. Liposomal adjuvant development for leishmaniasis vaccines.

    PubMed

    Askarizadeh, Anis; Jaafari, Mahmoud Reza; Khamesipour, Ali; Badiee, Ali

    2017-08-01

    Leishmaniasis is a parasitic disease that ranges in severity from skin lesions to fatality. Since long-lasting protection is induced upon recovery from cutaneous leishmaniasis, development of an effective vaccine is promising. However, there is no vaccine for use in humans yet. It seems limited efficacy in leishmaniasis vaccines is due to lack of an appropriate adjuvant or delivery system. Hence, the use of particulate adjuvants such as liposomes for effective delivery to the antigen presenting cells (APCs) is a valuable strategy to enhance leishmaniasis vaccine efficacy. The extraordinary versatility of liposomes because of their unique amphiphilic and biphasic nature allows for using antigens or immunostimulators within the core, on the surface or within the bilayer, and modulates both the magnitude and the T-helper bias of the immune response. In this review article, we attempt to summarize the role of liposomal adjuvants in the development of Leishmania vaccines and describe the main physicochemical properties of liposomes like phospholipid composition, surface charge, and particle size during formulation design. We also suggest potentially useful formulation strategies in order for future experiments to have a chance to succeed as liposomal vaccines against leishmaniasis.

  20. Liposomal adjuvant development for leishmaniasis vaccines

    PubMed Central

    Askarizadeh, Anis; Jaafari, Mahmoud Reza; Khamesipour, Ali; Badiee, Ali

    2017-01-01

    Leishmaniasis is a parasitic disease that ranges in severity from skin lesions to fatality. Since long-lasting protection is induced upon recovery from cutaneous leishmaniasis, development of an effective vaccine is promising. However, there is no vaccine for use in humans yet. It seems limited efficacy in leishmaniasis vaccines is due to lack of an appropriate adjuvant or delivery system. Hence, the use of particulate adjuvants such as liposomes for effective delivery to the antigen presenting cells (APCs) is a valuable strategy to enhance leishmaniasis vaccine efficacy. The extraordinary versatility of liposomes because of their unique amphiphilic and biphasic nature allows for using antigens or immunostimulators within the core, on the surface or within the bilayer, and modulates both the magnitude and the T-helper bias of the immune response. In this review article, we attempt to summarize the role of liposomal adjuvants in the development of Leishmania vaccines and describe the main physicochemical properties of liposomes like phospholipid composition, surface charge, and particle size during formulation design. We also suggest potentially useful formulation strategies in order for future experiments to have a chance to succeed as liposomal vaccines against leishmaniasis. PMID:29201374

  1. Obstacles to developing vaccines for the Third World.

    PubMed

    Robbins, A; Freeman, P

    1988-11-01

    Despite the tremendous strides in global immunization in less developed countries (LDCs) in the last 25 years, much remains to be done and the momentum has slowed. Vaccination programs continue to prove that they are less expensive, easier to implement, and in some cases more effective than other public health programs. Therefore it is imperative to produce and deliver new or improved vaccines to LDCs to prevent many infectious diseases and save the lives of children. Yet economic and political obstacles impede the development of these vaccines, even though the scientific know-how already exists. Manufacturers of vaccines that have been around for a long time and used widely in developed nations have often sold these vaccines to international agencies, such as WHO, at production cost. They do this because they have already recouped research & development (R&D) costs. When it comes to R&D of new vaccines, however, manufacturers are generally unwilling to invest time and money into R&D since they may not recoup their costs and make a profit. International agencies do not have the money to pay the high prices charged by manufacturers. Instead of the public health community in LDCs deciding on the development of new vaccines, the decision is left almost entirely in the hands of a few institutes or commercial manufacturers in the developed world. Other than continuing with the status quo, however, possible solutions do exist. For example, the UN could create an institute to develop and manufacture its own vaccines. Another possibility is that R&D and production of vaccines for diseases prevalent in an LDC or region could take place within that specified area.

  2. Carbohydrate-based vaccine adjuvants - discovery and development.

    PubMed

    Hu, Jing; Qiu, Liying; Wang, Xiaoli; Zou, Xiaopeng; Lu, Mengji; Yin, Jian

    2015-10-01

    The addition of a suitable adjuvant to a vaccine can generate significant effective adaptive immune responses. There is an urgent need for the development of novel po7tent and safe adjuvants for human vaccines. Carbohydrate molecules are promising adjuvants for human vaccines due to their high biocompatibility and good tolerability in vivo. The present review covers a few promising carbohydrate-based adjuvants, lipopolysaccharide, trehalose-6,6'-dibehenate, QS-21 and inulin as examples, which have been extensively studied in human vaccines in a number of preclinical and clinical studies. The authors discuss the current status, applications and strategies of development of each adjuvant and different adjuvant formulation systems. This information gives insight regarding the exciting prospect in the field of carbohydrate-based adjuvant research. Carbohydrate-based adjuvants are promising candidates as an alternative to the Alum salts for human vaccines development. Furthermore, combining two or more adjuvants in one formulation is one of the effective strategies in adjuvant development. However, further research efforts are needed to study and develop novel adjuvants systems, which can be more stable, potent and safe. The development of synthetic carbohydrate chemistry can improve the study of carbohydrate-based adjuvants.

  3. Vaccines against biologic agents: uses and developments.

    PubMed

    Ales, Noel C; Katial, Rohit K

    2004-03-01

    Although the Geneva protocol that prohibits the use of chemical and biologic weapons was ratified in 1925, many countries failed to accept this protocol: others stipulated retaliation, and some, like the United States, did not ratify the protocol for decades. This delay allowed the continued development of chemical and biologic agents. Members of the health care community are responsible for determining the best way to protect society from the potentially devastating effects of these biologic agents. Ideally,these diseases would be prevented from ever developing into systemic illnesses. In the past, vaccination has been a successful means of eradicating disease. Vaccines remain a hopeful therapy for the future, but time is short,and there are many obstacles.Information regarding bioterrorism agents and their treatments comes mainly from dated data or from in vitro or animal studies that may not apply to human treatment and disease. Additionally, the current threat of bioterrorism does not allow enough time for accurate, well-designed,controlled studies in humans before the release of investigational vaccines. Furthermore, some human studies would not be safe or ethical. Finally,many members of society suffer from illnesses that would put them at high risk to receive prophylactic vaccination. It is therefore naive to believe that vaccines would be the ultimate protection from these agents. In addition to vaccine development, there must be concurrent investigations into disease management and treatment. Even in instances in which vaccination is known to be an effective means of disease protection. biologic agents may be presented in a manner that renders vaccines ineffective. Virulent strains of organisms may be used, more than one organism may be used in tandem to increase virulence, and strains may be selected for antibiotic and vaccine resistance. Genetically engineered strains may use virulence factors other than those targeted in vaccines, and high

  4. Development of Zika Virus Vaccines

    PubMed Central

    Makhluf, Huda; Shresta, Sujan

    2018-01-01

    Zika virus (ZIKV) is a mosquito-borne flavivirus that emerged as a global threat following the most recent outbreak in Brazil in 2015. ZIKV infection of pregnant women is associated with fetal abnormalities such as microcephaly, and infection of adults can lead to Guillain–Barré syndrome, an autoimmune disease characterized by neurological deficits. Although there are currently licensed vaccines for other flaviviruses, there remains an urgent need for preventative vaccines against ZIKV infection. Herein we describe the current efforts to accelerate the development of ZIKV vaccines using various platforms, including live attenuated virus, inactivated virus, DNA and RNA, viral vectors, and in silico-predicted immunogenic viral epitopes. Many of these approaches have leveraged lessons learned from past experience with Dengue and other flavivirus vaccines. PMID:29346287

  5. Innovations in vaccine development: can regulatory authorities keep up?

    PubMed

    Cox, Manon M J; Onraedt, Annelies

    2012-10-01

    Vaccine Production Summit San Francisco, CA, USA, 4-6 June 2012 IBC's 3rd Vaccine Production Summit featured 28 presentations discussing regulatory challenges in vaccine development, including the use of adjuvants, vaccine manufacturing and technology transfer, process development for vaccines and the role of quality by design, how to address vaccine stability, and how vaccine development timelines can be improved. The conference was run in parallel with the single-use applications for Biopharmaceutical Manufacturing conference. Approximately 250 attendees from large pharmaceutical companies, large and small biotech companies, vendors and a more limited number from academia were allowed to access sessions of either conference, including one shared session. This article summarizes the recurring themes across various presentations.

  6. Influenza Vaccines: Unmet Needs and Recent Developments

    PubMed Central

    Noh, Ji Yun

    2013-01-01

    Influenza is a worldwide public health concern. Since the introduction of trivalent influenza vaccine in 1978, vaccination has been the primary means of prevention and control of influenza. Current influenza vaccines have moderate efficacy, good safety, and acceptable tolerability; however, they have unsatisfactory efficacy in older adults, are dependent on egg supply for production, and are time-consuming to manufacture. This review outlines the unmet medical needs of current influenza vaccines. Recent developments in influenza vaccines are also described. PMID:24475351

  7. HIV vaccine development: would more (public) money bring quicker results?

    PubMed

    Winsbury, R

    1999-01-01

    Globally, $200-250 million/year are devoted to HIV vaccine research. Most of those funds pay for basic research rather than product development. Moreover, most of the funds are aimed at the HIV strain commonly found in the US and Europe, and not at the strains common to Africa and other developing countries. While US President Bill Clinton set in 1997 a 10-year target for the development of an HIV vaccine, that target date is looking increasingly unlikely. International vaccine and pharmaceutical companies typically drive vaccine research and development. However, concern over the ultimate profitability of developing and marketing an HIV vaccine, and the fear of major litigation should an eventual vaccine go awry have caused such firms to shy away from investing large amounts of money into HIV vaccine development. These companies somehow have to be attracted back into the field. A World Bank special task force is slated to present its report by mid-1999 on possible funding mechanisms to promote HIV vaccine development. It remains to be resolved whether public funds could and should be used, perhaps through a pooled international vaccine development fund. 2 new International AIDS Vaccine Initiative projects are described.

  8. Technology and tuberculosis control: the OUT-TB Web experience.

    PubMed

    Guthrie, Jennifer L; Alexander, David C; Marchand-Austin, Alex; Lam, Karen; Whelan, Michael; Lee, Brenda; Furness, Colin; Rea, Elizabeth; Stuart, Rebecca; Lechner, Julia; Varia, Monali; McLean, Jennifer; Jamieson, Frances B

    2017-04-01

    Develop a tool to disseminate integrated laboratory, clinical, and demographic case data necessary for improved contact tracing and outbreak detection of tuberculosis (TB). In 2007, the Public Health Ontario Laboratories implemented a universal genotyping program to monitor the spread of TB strains within Ontario. Ontario Universal Typing of TB (OUT-TB) Web utilizes geographic information system (GIS) technology with a relational database platform, allowing TB control staff to visualize genotyping matches and microbiological data within the context of relevant epidemiological and demographic data. OUT-TB Web is currently available to the 8 health units responsible for >85% of Ontario's TB cases and is a valuable tool for TB case investigation. Users identified key features to implement for application enhancements, including an e-mail alert function, customizable heat maps for visualizing TB and drug-resistant cases, socioeconomic map layers, a dashboard providing TB surveillance metrics, and a feature for animating the geographic spread of strains over time. OUT-TB Web has proven to be an award-winning application and a useful tool. Developed and enhanced using regular user feedback, future versions will include additional data sources, enhanced map and line-list filter capabilities, and development of a mobile app. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  9. Assessment of safety and interferon gamma responses of Mycobacterium bovis BCG vaccine in goat kids and milking goats.

    PubMed

    Pérez de Val, Bernat; Vidal, Enric; López-Soria, Sergio; Marco, Alberto; Cervera, Zoraida; Martín, Maite; Mercader, Irene; Singh, Mahavir; Raeber, Alex; Domingo, Mariano

    2016-02-10

    Vaccination of domestic animals has emerged as an alternative long-term strategy for the control of tuberculosis (TB). A trial under field conditions was conducted in a TB-free goat herd to assess the safety of the Mycobacterium bovis BCG vaccine. Eleven kids and 10 milking goats were vaccinated with BCG. Bacterial shedding and interferon gamma (IFN-γ) responses were monitored throughout the study. Comprehensive pathological examination and mycobacterial culture of target tissues were performed. BCG vaccine strain was only isolated from the draining lymph node of the injection site of a kid euthanized at week 8 post-vaccination. The remaining animals were euthanized at week 24. Six out of 20 showed small granulomas at the injection site. BCG shedding was not detected in either faeces or in milk throughout the study. All vaccinated kids showed BCG-induced IFN-γ responses at week 8 post-vaccination. BCG vaccination of goats showed no lack of biological safety for the animals, environment and public health, and local adverse reactions were negligible. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Reverse Vaccinology: Developing Vaccines in the Era of Genomics

    PubMed Central

    Sette, Alessandro; Rappuoli, Rino

    2012-01-01

    The sequence of microbial genomes made all potential antigens of each pathogen available for vaccine development. This increased by orders of magnitude potential vaccine targets in bacteria, parasites, and large viruses and revealed virtually all their CD4+ and CD8+ T cell epitopes. The genomic information was first used for the development of a vaccine against serogroup B meningococcus, and it is now being used for several other bacterial vaccines. In this review, we will first summarize the impact that genome sequencing has had on vaccine development, and then we will analyze how the genomic information can help further our understanding of immunity to infection or vaccination and lead to the design of better vaccines by diving into the world of T cell immunity. PMID:21029963

  11. Snapshot of Quantiferon TB gold testing in Northern Mexico.

    PubMed

    González-Salazar, F; Vargas-Villarreal, J; Garcialuna-Martínez, F J; Rivera, G; Moreno-Treviño, M G; Montfort-Gardeazabal, J M; Garcialuna-Martínez, E

    2011-12-01

    Most people infected with Mycobacterium tuberculosis have an asymptomatic condition named latent tuberculosis. These people do not have bacilli in the corporal secretions and are hard to diagnose by conventional laboratory tests. Diagnosis of latent tuberculosis infection (LTBI) in México is based on the tuberculin skin test (TST). This test has disadvantages, principally because the vaccine containing the Bacille Calmette-Guérin (BCG) is applied to 99% of this population and causes false positive TST outcomes. Recently, interferon-gamma release assays (IGRA) have been demonstrated to be a good test to detect latent tuberculosis with equal or better sensitivity to TST and without interference from BCG. However, in México the IGRA are an uncommon test due to the higher cost compared to TST. The main objective of this work was demonstrate the potential utility of the Quantiferon TB(®) gold in tube (QTB(®)-GIT) test to detect latent TB in a population from northern México. Samples from 106 subjects with close contact, or without contact, with actively infected TB patients were tested to detect LTBI. Our results show a significant difference between individuals in close contact with active TB patients (39.7%) compared to those without contact (3.2%), p < 0.01. The concordance between TST and QTB(®)-GIT was poor (κ = 0.31). Our preliminary results show that the QTB(®)-GIT has better capacity than TST to detect latent tuberculosis infection. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Testing a molasses-based bait for oral vaccination of white-tailed deer (Odocoileus virginianus) against Mycobacterium bovis

    USDA-ARS?s Scientific Manuscript database

    White-tailed deer (Odocoileus virginianus) in Michigan, USA are wildlife reservoirs of bovine tuberculosis (bTB) with documented spread to cattle. In vaccine efficacy trials, Mycobacterium bovis bacillus Calmette Guerin (BCG) administered orally reduces colonization and bTB-associated lesions in whi...

  13. A comparison of wildlife control and cattle vaccination as methods for the control of bovine tuberculosis.

    PubMed Central

    Kao, R. R.; Roberts, M. G.

    1999-01-01

    The Australian brushtail possum is the major source of infection for new cases of bovine tuberculosis in cattle in New Zealand. Using hypothetical values for the cost of putative cattle and possum Tb vaccines, the relative efforts required to eradicate Tb in cattle using possum culling, possum vaccination or cattle vaccination are compared. For realistic assumed costs for 1080 poison bait, possum culling is found to be a cost-effective strategy compared to cattle vaccination if the required control area is below 13 ha per cattle herd, while possum vaccination is cost-effective for control areas of less than 3 ha per herd. Examination of other considerations such as the possible roles of possum migration and heterogeneities in possum population density suggest that each control strategy may be superior under different field conditions. Finally, the roles of the possum in New Zealand, and the Eurasian badger in Great Britain and Ireland in the transmission of bovine tuberculosis to cattle are compared. PMID:10459656

  14. Progress in the Development of a Cervical Cancer Vaccine

    PubMed Central

    Winters, Ursula; Roden, Richard; Kitchener, Henry; Stern, Peter

    2006-01-01

    Persistent infection by ‘high risk’ genotypes of human papilloma virus (HPV) is necessary but not sufficient for the development of over 98% of cervical cancers. Thus the development of vaccines that prevent HPV transmission represent an important opportunity to prevent cervical cancer. There are several prophylactic HPV vaccine formulations based upon L1 virus-like particles (VLPs) currently in phase III trials and recently released data are extremely promising. However, many practical issues surrounding implementation of these vaccines need to be addressed including, who and when to vaccinate, duration of protection, and integration with current screening programs. The vaccines currently being evaluated target the two most prevalent high risk HPV types which are responsible for approximately 70% of cervical cancers. To increase the breadth of protection, it is likely that L1 VLPs of other viral subtypes must be included, although vaccines targeting the conserved regions of the L2 minor capsid protein warrant further exploration in this regard. In addition the vaccines nearing licensing will not combat established HPV-related disease and a therapeutic vaccine, of which there are several candidates in early stages of development, would be desirable. This review discusses the background to and progress in vaccine development and the issues surrounding the introduction of HPV vaccines. PMID:18360601

  15. The association between ARV and TB drug resistance on TB treatment outcome among Kazakh TB/HIV patients.

    PubMed

    Mishkin, Kathryn; Alaei, Kamiar; Alikeyeva, Elmira; Paynter, Christopher; Aringazina, Altyn; Alaei, Arash

    2018-02-26

    TB drug resistance poses a serious threat to the public health of Kazakhstan. This paper presents findings related to TB treatment outcome and drug resistant status among people coinfected with HIV and TB in Kazakhstan. Cohort study using data were provided by the Kazakhstan Ministry of Health's National Tuberculosis Program for 2014 and 2015. Chi-square and logistical regression were performed to understand factors associated with drug resistant TB status and TB treatment outcome. In bivariate analysis, drug resistant status was significantly associated with year of TB diagnosis (p=0.001) viral load (p=0.03). TB treatment outcome was significantly associated with age at diagnosis (p=01), ARV treatment (p <0.0001), and TB drug resistant status (p=0.02). In adjusted analysis, drug resistance was associated with increased odds of successful completion of treatment with successful result compared to treatment failure (OR 6.94, 95% CI: 1.39-34.44) CONCLUSIONS: Our results suggest that being drug resistant is associated with higher odds of completing treatment with successful outcome, even when controlling for receipt of ARV therapy. Copyright © 2018. Published by Elsevier Ltd.

  16. Dengue vaccines: recent developments, ongoing challenges and current candidates

    PubMed Central

    McArthur, Monica A.; Sztein, Marcelo B.; Edelman, Robert

    2013-01-01

    Summary Dengue is among the most prevalent and important arbovirus diseases of humans. In order to effectively control this rapidly spreading disease, control of the vector mosquito and a safe and efficacious vaccine are critical. Despite considerable efforts, the development of a successful vaccine has remained elusive. Multiple factors have complicated the creation of a successful vaccine, not the least of which are the complex, immune-mediated responses against four antigenically distinct serotypes necessitating a tetravalent vaccine providing long lasting protective immunity. Despite the multiple impediments, there are currently many promising vaccine candidates in pre-clinical and clinical development. Here we review the recent advances in dengue virus vaccine development and briefly discuss the challenges associated with the use of these vaccines as a public health tool. PMID:23984962

  17. Strategic priorities for respiratory syncytial virus (RSV) vaccine development

    PubMed Central

    Anderson, L.J.; Dormitzer, P.R.; Nokes, D.J.; Rappuoli, R.; Roca, A.; Graham, B.S.

    2013-01-01

    Although RSV has been a high priority for vaccine development, efforts to develop a safe and effective vaccine have yet to lead to a licensed product. Clinical and epidemiologic features of RSV disease suggest there are at least 4 distinct target populations for vaccines, the RSV naïve young infant, the RSV naïve child ≥6 months of age, pregnant women (to provide passive protection to newborns), and the elderly. These target populations raise different safety and efficacy concerns and may require different vaccination strategies. The highest priority target population is the RSV naïve child. The occurrence of serious adverse events associated with the first vaccine candidate for young children, formalin inactivated RSV (FI-RSV), has focused vaccine development for the young RSV naïve child on live virus vaccines. Enhanced disease is not a concern for persons previously primed by a live virus infection. A variety of live-attenuated viruses have been developed with none yet achieving licensure. New live-attenuated RSV vaccines are being developed and evaluated that maybe sufficiently safe and efficacious to move to licensure. A variety of subunit vaccines are being developed and evaluated primarily for adults in whom enhanced disease is not a concern. An attenuated parainfluenza virus 3 vector expressing the RSV F protein was evaluated in RSV naïve children. Most of these candidate vaccines have used the RSV F protein in various vaccine platforms including virus-like particles, nanoparticles, formulated with adjuvants, and expressed by DNA or virus vectors. The other surface glycoprotein, the G protein, has also been used in candidate vaccines. We now have tools to make and evaluate a wide range of promising vaccines. Costly clinical trials in the target population are needed to evaluate and select candidate vaccines for advancement to efficacy trials. Better data on RSV-associated mortality in developing countries, better estimates of the risk of long term

  18. Development of Stable Influenza Vaccine Powder Formulations: Challenges and Possibilities

    PubMed Central

    Amorij, J-P.; Huckriede, A.; Wilschut, J.; Frijlink, H. W.

    2008-01-01

    Influenza vaccination represents the cornerstone of influenza prevention. However, today all influenza vaccines are formulated as liquids that are unstable at ambient temperatures and have to be stored and distributed under refrigeration. In order to stabilize influenza vaccines, they can be brought into the dry state using suitable excipients, stabilizers and drying processes. The resulting stable influenza vaccine powder is independent of cold-chain facilities. This can be attractive for the integration of the vaccine logistics with general drug distribution in Western as well as developing countries. In addition, a stockpile of stable vaccine formulations of potential vaccines against pandemic viruses can provide an immediate availability and simple distribution of vaccine in a pandemic outbreak. Finally, in the development of new needle-free dosage forms, dry and stable influenza vaccine powder formulations can facilitate new or improved targeting strategies for the vaccine compound. This review represents the current status of dry stable inactivated influenza vaccine development. Attention is given to the different influenza vaccine types (i.e. whole inactivated virus, split, subunit or virosomal vaccine), the rationale and need for stabilized influenza vaccines, drying methods by which influenza vaccines can be stabilized (i.e. lyophilization, spray drying, spray-freeze drying, vacuum drying or supercritical fluid drying), the current status of dry influenza vaccine development and the challenges for ultimate market introduction of a stable and effective dry-powder influenza vaccine. PMID:18338241

  19. Developing Zika vaccines: the lessons for disease X.

    PubMed

    Barrett, Alan D T

    2018-06-26

    There is an urgent need to develop vaccines against emerging diseases, including those caused by pathogens that are currently unknown to cause human disease, termed 'disease X'. Here, Zika virus infection is considered as an example of disease X. The speed of Zika vaccine development provides optimism for our ability to prepare vaccines against unknown pathogens.

  20. Developing Countries Vaccine Manufacturers Network: doing good by making high-quality vaccines affordable for all.

    PubMed

    Pagliusi, Sonia; Leite, Luciana C C; Datla, Mahima; Makhoana, Morena; Gao, Yongzhong; Suhardono, Mahendra; Jadhav, Suresh; Harshavardhan, Gutla V J A; Homma, Akira

    2013-04-18

    The Developing Countries Vaccine Manufacturers Network (DCVMN) is a unique model of a public and private international alliance. It assembles governmental and private organizations to work toward a common goal of manufacturing and supplying high-quality vaccines at affordable prices to protect people around the world from known and emerging infectious diseases. Together, this group of manufacturers has decades of experience in manufacturing vaccines, with technologies, know-how, and capacity to produce more than 40 vaccines types. These manufacturers have already contributed more than 30 vaccines in various presentations that have been prequalified by the World Health Organization for use by global immunization programmes. Furthermore, more than 45 vaccines are in the pipeline. Recent areas of focus include vaccines to protect against rotavirus, human papillomavirus (HPV), Japanese encephalitis, meningitis, hepatitis E, poliovirus, influenza, and pertussis, as well as combined pentavalent vaccines for children. The network has a growing number of manufacturers that produce a growing number of products to supply the growing demand for vaccines in developing countries. Copyright © 2013. Published by Elsevier Ltd.

  1. Progress towards development of an HIV vaccine: report of the AIDS Vaccine 2009 Conference.

    PubMed

    Ross, Anna Laura; Bråve, Andreas; Scarlatti, Gabriella; Manrique, Amapola; Buonaguro, Luigi

    2010-05-01

    The search for an HIV/AIDS vaccine is steadily moving ahead, generating and validating new concepts in terms of novel vectors for antigen delivery and presentation, new vaccine and adjuvant strategies, alternative approaches to design HIV-1 antigens for eliciting protective cross-neutralising antibodies, and identification of key mechanisms in HIV infection and modulation of the immune system. All these different perspectives are contributing to the unprecedented challenge of developing a protective HIV-1 vaccine. The high scientific value of this massive effort is its great impact on vaccinology as a whole, providing invaluable scientific information for the current and future development of new preventive vaccine as well as therapeutic knowledge-based infectious-disease and cancer vaccines. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Framework of behavioral indicators for outcome evaluation of TB health promotion: a Delphi study of TB suspects and Tb patients.

    PubMed

    Li, Ying; Ehiri, John; Hu, Daiyu; Zhang, Yanqi; Wang, Qingya; Zhang, Shun; Cao, Jia

    2014-05-16

    Health promotion for prevention and control of Tuberculosis (TB) is implemented worldwide because of its importance, but few reports have evaluated its impact on behavior due to a lack of standard outcome indicators. The objective of this study was to establish a framework of behavioral indicators for outcome evaluation of TB health promotion among TB suspects and patients. A two-round modified Delphi method involving sixteen TB control experts was used to establish a framework of behavioral indicators for outcome evaluation of TB health promotion targeted at TB suspects and patients. Sixteen of seventeen invited experts in TB control (authority score of 0.91 on a 1.0 scale) participated in round 1 survey. All sixteen experts also participated in a second round survey. After two rounds of surveys and several iterations among the experts, there was consensus on a framework of indicators for measuring outcomes of TB health promotion for TB suspects and patients. For TB suspects, the experts reached consensus on 2 domains ("Healthcare seeking behavior" and "Transmission prevention"), 3 subdomains ("Seeking care after onset of TB symptoms", "Pathways of seeking care" and "Interpersonal contact etiquette"), and 8 indicators (including among others, "Length of patient delay"). For TB patients, consensus was reached on 3 domains ("Adherence to treatment", "Healthy lifestyle" and "Transmission prevention"), 8 subdomains (including among others, "Adherence to their medication"), and 14 indicators (including "Percentage of patients who adhered to their medication"). Operational definitions and data sources were provided for each indicator. The findings of this study provide the basis for debate among international experts on a framework for achieving global consensus on outcome indicators for TB health promotion interventions targeted at TB patients and suspects. Such consensus will help to increase effectiveness of TB health promotion, while ensuring international

  3. Varicella and herpes zoster vaccine development: lessons learned.

    PubMed

    Warren-Gash, Charlotte; Forbes, Harriet; Breuer, Judith

    2017-12-01

    Before vaccination, varicella zoster virus (VZV), which is endemic worldwide, led to almost universal infection. This neurotropic virus persists lifelong by establishing latency in sensory ganglia, where its reactivation is controlled by VZV-specific T-cell immunity. Lifetime risk of VZV reactivation (zoster) is around 30%. Vaccine development was galvanised by the economic and societal burden of VZV, including debilitating zoster complications that largely affect older individuals. Areas covered: We describe the story of development, licensing and implementation of live attenuated vaccines against varicella and zoster. We consider the complex backdrop of VZV virology, pathogenesis and immune responses in the absence of suitable animal models and examine the changing epidemiology of VZV disease. We review the vaccines' efficacy, safety, effectiveness and coverage using evidence from trials, observational studies from large routine health datasets and clinical post-marketing surveillance studies and outline newer developments in subunit and inactivated vaccines. Expert commentary: Safe and effective, varicella and zoster vaccines have already made major inroads into reducing the burden of VZV disease globally. As these live vaccines have the potential to reactivate and cause clinical disease, developing alternatives that do not establish latency is an attractive prospect but will require better understanding of latency mechanisms.

  4. Malnutrition and vaccination in developing countries

    PubMed Central

    Prendergast, Andrew J.

    2015-01-01

    Malnutrition contributes to an estimated 45% of deaths among children under 5 years of age in developing countries, predominantly due to infections. Malnourished children therefore stand to benefit hugely from vaccination, but malnutrition has been described as the most common immunodeficiency globally, suggesting that they may not be able to respond effectively to vaccines. The immunology of malnutrition remains poorly characterized, but is associated with impairments in mucosal barrier integrity, and innate and adaptive immune dysfunction. Despite this, the majority of malnourished children can mount a protective immune response following vaccination, although the timing, quality and duration of responses may be impaired. This paper reviews the evidence for vaccine immunogenicity in malnourished children, discusses the importance of vaccination in prevention of malnutrition and highlights evidence gaps in our current knowledge. PMID:25964453

  5. Monodisperse, Uniformly-Shaped Particles for Controlled Respiratory Vaccine Delivery

    NASA Astrophysics Data System (ADS)

    Fromen, Catherine Ann

    The majority of the world's most infectious diseases occur at the air-tissue interface called the mucosa, including HIV/AIDS, tuberculosis, measles, and bacterial or viral gut and respiratory infections. Despite this, vaccines have generally been developed for the systemic immune system and fail to provide protection at the mucosal site. Vaccine delivery directly to the lung mucosa could provide superior lung protection for many infectious diseases, such as TB or influenza, as well as systemic and therapeutic vaccines for diseases such as Dengue fever, asthma, or cancer. Specifically, precision engineered biomaterials are believed to offer tremendous opportunities for a new generation of vaccines. The goal of this approach is to leverage naturally occurring processes of the immune system to produce memory responses capable of rapidly destroy virulent pathogens without harmful exposure. Considerable knowledge of biomaterial properties and their interaction with the immune system of the lung is required for successful translation. The overall goal of this work was to fabricate and characterize nano- and microparticles using the Particle Replication In Non-wetting Templates (PRINT) fabrication technique and optimize them as pulmonary vaccine carriers. (Abstract shortened by ProQuest.).

  6. Development of pediatric vaccine recommendations and policies.

    PubMed

    Pickering, Larry K; Orenstein, Walter A

    2002-07-01

    A significant decrease in each vaccine-preventable disease has occurred since the introduction of the respective immunizations now included in the recommended childhood immunization schedule. The process through which a vaccine must travel from development to approval and implementation is complex. Hurdles include receiving approval from several advisory committees, government agencies, and professional organizations. At each step in the process, data regarding safety, immunogenicity, and efficacy are evaluated continuously and rigorously. Once a vaccine is approved by the Food and Drug Administration (FDA) and incorporated into the recommended childhood immunization schedule, continuing issues include those that deal with supply, safety, effectiveness, and financing. The logistics of development and implementation of pediatric vaccine recommendations and policies are reviewed.

  7. A world of cities and the end of TB

    PubMed Central

    Prasad, Amit; Ross, Alex; Rosenberg, Paul; Dye, Christopher

    2016-01-01

    The WHO's End TB Strategy aims to reduce TB deaths by 95% and incidence by 90% between 2015 and 2035. As the world rapidly urbanizes, more people could have access to better infrastructure and services to help combat poverty and infectious diseases, including TB. And yet large numbers of people now live in overcrowded slums, with poor access to urban health services, amplifying the burden of TB. An alignment of the Sustainable Development Goals (SDGs) for health and for urban development provides an opportunity to accelerate the overall decline in infection and disease, and to create cities free of TB. PMID:26884491

  8. Zika Vaccine Development: Flavivirus Foils

    DTIC Science & Technology

    2016-09-01

    broader community’s extensive experience with Dengue virus vaccine development and with the pros and cons of different vaccine platforms has led to...the public. Perhaps the best understood aspect of Zika virus is its close relation to Dengue virus and other flaviviruses. The close...which would significantly advance our understanding of the epidemiology of Zika virus. However, the cross-reactivity of antibody elicited by Dengue

  9. Status of vaccine research and development of vaccines for Staphylococcus aureus.

    PubMed

    Giersing, Birgitte K; Dastgheyb, Sana S; Modjarrad, Kayvon; Moorthy, Vasee

    2016-06-03

    Staphylococcus aureus is a highly versatile gram positive bacterium that is resident as an asymptomatic colonizer on the skin and in the nasopharynx of approximately 30% of individuals. Nasopharyngeal colonization is a risk for acquiring S. aureus infections, which can cause a range of clinical symptoms that are commonly associated with skin and soft-tissue infections. The emergence of S. aureus strains that are highly resistant to antimicrobials has recently become a major public health concern. In low-income countries the incidence of S. aureus disease is highest in neonates and children up to one year of age and mortality rates are estimated to be up to 50%. In the United States, S. aureus infection accounts for approximately 300,000 hospitalizations per year. A vaccine against multi-drug resistant S. aureus, therefore, is urgently needed. Two vaccine candidates have previously been evaluated in late-stage clinical trials but have not demonstrated efficacy. At present, one vaccine candidate and two monoclonal antibody are undergoing clinical evaluation in target groups at high risk for S. aureus infection. This review provides an overview of current vaccine development efforts and presents the major technical and regulatory challenges to developing a licensed S. aureus vaccine. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  10. New drugs and regimens for treatment of TB

    PubMed Central

    Leibert, Eric; Rom, William N

    2013-01-01

    Tools for effective TB control have been available for years. Case finding, active medications, case management and directly observed therapy are the foundations for the management of TB. The current TB epidemic, centered in resource-limited settings is fueled by the HIV-1 epidemic. Lack of ability to diagnose and treat drug-resistant TB has led to development of more extensive patterns of resistance. Among the currently available drugs, there is reason to hope that rifamycins paired with fluoroquinolones will lead to shorter treatment regimens for drug-susceptible TB. As the result of novel public-private collaborations and investments of resources, new drugs are being developed. These include TMC207, already shown to have activity early in the treatment of multidrug-resistant TB and others that are likely to be active against persistor organisms, and have the prospect to dramatically shorten treatment courses for active and latent TB. Given that these drugs have novel mechanisms of action, combinations have the prospect to be highly active even against multidrug-resistant organisms. PMID:20586565

  11. A history of the development of Brucella vaccines.

    PubMed

    Avila-Calderón, Eric Daniel; Lopez-Merino, Ahidé; Sriranganathan, Nammalwar; Boyle, Stephen M; Contreras-Rodríguez, Araceli

    2013-01-01

    Brucellosis is a worldwide zoonosis affecting animal and human health. In the last several decades, much research has been performed to develop safer Brucella vaccines to control the disease mainly in animals. Till now, no effective human vaccine is available. The aim of this paper is to review and discuss the importance of methodologies used to develop Brucella vaccines in pursuing this challenge.

  12. The development of new phosphors of Tb3+/Eu3+ co-doped Gd3Al5O12 with tunable emission

    NASA Astrophysics Data System (ADS)

    Teng, Xin; Wang, Wenzhi; Cao, Zhentao; Li, Jinkai; Duan, Guangbin; Liu, Zongming

    2017-07-01

    The gadolinium aluminum garnets Gd3Al5O12 (GdAG) activated with Tb3+/Eu3+ were successfully prepared via co-precipitation method at 1500 °C in this work. The crystal structure stabilization, elements analysis, microphotograph, PL/PLE spectra, decay behavior and quantum efficiency were discussed in detail. The metastable GdAG compounds been effectively stabilized by doping with smaller 10 at.% Tb3+, which then allows the development of new phosphors of (Gd0.9-xTb0.1Eux)3Al5O12 (GdAG:Tb3+/Eu3+, x = 0-0.03) for opto-functionality explorations. The PLE/PL spectra displays that the strongest PLE peak was located at ∼276 nm, which overlaps the 8S7/2 → 6IJ transition of Gd3+. Under 276 nm excitation, the phosphors exhibited both Tb3+ and Eu3+ emissions at 548 nm (green, 5D4 → 7F5 transition of Tb3+) and 592 nm (orange-red, 5D0 → 7F1 transition of Eu3+), respectively. The emission intensities of Tb3+ and Eu3+ remarkably varied with the Eu3+ incorporation. As a consequence, the emission color can be readily tuned from approximately green to orange-red. Fluorescence decay analysis found that the lifetime for the Tb3+ emission rapidly decreased conforming to the Tb3+ → Eu3+ energy transfer, and the energy transfer efficiency was calculated. Owing to the Gd3+ → Eu3+ and Gd3+ → Tb3+ energy transfer, the emission intensities of Tb3+ and Eu3+ in (Gd0.9-xTb0.1Eux)AG phosphor were higher than (Y0.87Tb0.1Eu0.03)AG and (Lu0.87Tb0.1Eu0.03)AG system. The (Gd0.9-xTb0.1Eux)AG garnet phosphors developed in this work may serve as a new type of phosphor which hopefully meets the requirements of various lighting and optical display applications.

  13. Epidemiology of HIV-TB in Asia.

    PubMed

    Narain, Jai P; Lo, Ying-Ru

    2004-10-01

    Tuberculosis (TB) has, for centuries, continued to remain a public health problem of enormous importance, particularly in the developing world, taking a heavy toll of those at their prime of life. The emergence of human immunodeficiency virus (HIV infection) and its close association with TB poses an even greater challenge to the health systems in general and TB programmes in particular, in African and Asian countries. HIV is considered to be the most potent risk factor for progression to active TB among those infected both with TB and HIV; as a result, TB is the most common life threatening opportunistic infection associated with HIV, and biggest cause of death among patients with acquired immunodeficiency syndrome (AIDS). In areas hard-hit by HIV, TB is increasing, leading to greater case load, thereby overstretching the already fragile health infrastructure. The deadly relationship between HIV and TB, each potentiating the effect of the other, requires a clearly defined strategy taking into consideration the natural history of the co-infection and its progression to clinical TB (and AIDS). It is clear that the only way to fight this is by bringing the two programmes to join forces and work creatively and innovatively. The strategy should include not only preventing HIV through community-based behavioural interventions and limiting progression to clinical TB through the use of isoniazid preventive therapy, but also early diagnosis and treatment of HIV-associated TB and AIDS using DOTS strategy and combination antiretroviral therapy respectively. The strategy probably would not succeed unless both the programmes are first strengthened before attempting to forge collaboration based on mutual strengths and comparative advantages. In addition, mobilizing national and international response, building partnerships and mobilizing resources will help a great deal in mounting an appropriate and effective response to HIV/TB in the Asian context.

  14. Malaria vaccine development and how external forces shape it: an overview.

    PubMed

    Lorenz, Veronique; Karanis, Gabriele; Karanis, Panagiotis

    2014-06-30

    The aim of this paper is to analyse the current status and scientific value of malaria vaccine approaches and to provide a realistic prognosis for future developments. We systematically review previous approaches to malaria vaccination, address how vaccine efforts have developed, how this issue may be fixed, and how external forces shape vaccine development. Our analysis provides significant information on the various aspects and on the external factors that shape malaria vaccine development and reveal the importance of vaccine development in our society.

  15. Typhoid fever & vaccine development: a partially answered question.

    PubMed

    Marathe, Sandhya A; Lahiri, Amit; Negi, Vidya Devi; Chakravortty, Dipshikha

    2012-01-01

    Typhoid fever is a systemic disease caused by the human specific Gram-negative pathogen Salmonella enterica serovar Typhi (S. Typhi). The extra-intestinal infections caused by Salmonella are very fatal. The incidence of typhoid fever remains very high in impoverished areas and the emergence of multidrug resistance has made the situation worse. To combat and to reduce the morbidity and mortality caused by typhoid fever, many preventive measures and strategies have been employed, the most important being vaccination. In recent years, many Salmonella vaccines have been developed including live attenuated as well as DNA vaccines and their clinical trials have shown encouraging results. But with the increasing antibiotic resistance, the development of potent vaccine candidate for typhoid fever is a need of the hour. This review discusses the latest trends in the typhoid vaccine development and the clinical trials which are underway.

  16. Prophylactic Effect of a Therapeutic Vaccine against TB Based on Fragments of Mycobacterium tuberculosis

    PubMed Central

    Cáceres, Neus; Pinto, Sergio; Díaz, Jorge; Cardona, Pere-Joan

    2011-01-01

    The prophylactic capacity of the RUTI® vaccine, based on fragmented cells of Mycobacterium tuberculosis, has been evaluated in respect to aerosol challenge with virulent bacilli. Subcutaneous vaccination significantly reduced viable bacterial counts in both lungs and spleens of C57Bl mice, when challenged 4 weeks after vaccination. RUTI® protected the spleen less than BCG. Following a 9 month vaccination-challenge interval, protection was observed for the lungs, but not for the spleen. Survival of infected guinea pigs was prolonged by vaccination given 5 weeks before challenge. Inoculations of RUTI® shortly after infection significantly reduced the viable bacterial counts in the lungs, when compared with infected control mice. Thus, vaccination by RUTI® has potential for both the prophylaxis and immunotherapy of tuberculosis. PMID:21647222

  17. Prophylactic effect of a therapeutic vaccine against TB based on fragments of Mycobacterium tuberculosis.

    PubMed

    Vilaplana, Cristina; Gil, Olga; Cáceres, Neus; Pinto, Sergio; Díaz, Jorge; Cardona, Pere-Joan

    2011-01-01

    The prophylactic capacity of the RUTI® vaccine, based on fragmented cells of Mycobacterium tuberculosis, has been evaluated in respect to aerosol challenge with virulent bacilli. Subcutaneous vaccination significantly reduced viable bacterial counts in both lungs and spleens of C57Bl mice, when challenged 4 weeks after vaccination. RUTI® protected the spleen less than BCG. Following a 9 month vaccination-challenge interval, protection was observed for the lungs, but not for the spleen. Survival of infected guinea pigs was prolonged by vaccination given 5 weeks before challenge. Inoculations of RUTI® shortly after infection significantly reduced the viable bacterial counts in the lungs, when compared with infected control mice. Thus, vaccination by RUTI® has potential for both the prophylaxis and immunotherapy of tuberculosis.

  18. Development of male contraceptive vaccine--a perspective.

    PubMed

    Moudgal, N R; Jeyakumar, M; Krishnamurthy, H N; Sridhar, S; Krishnamurthy, H; Martin, F

    1997-01-01

    This paper reviews the recent advances that have occurred in the area of development of a male contraceptive vaccine. The vaccine candidates considered for review are hormone/hormone receptor-based proteins including luteinizing hormone-releasing hormone (LHRH)/LH, follicle stimulating hormone (FSH), as well as LH and FSH receptor proteins. The review also highlights the advances in our basic understanding of gonadotrophin action which have led to development of these vaccines. Focus is mainly on studies in the non-human primate which may be directly relevant to projected studies in the human. The data indicate that the vaccines are well tolerated by the primate (including the human based on limited data) and do not give rise to any known toxic symptoms or immediate health hazards. The response to the immunogen has been uniform and it may be possible to increase antibody titres as well as prolong the immune response by adding acceptable immune stimulators to the adjuvant cocktail and developing better immunization schedules or immunogen delivery systems. Contraceptive vaccines for the male are a feasible proposition and attention should now be focussed on evaluating carefully the bioefficacy of antibodies raised to recombinant ovine FSHbeta or FSH receptor protein fragments in both human and non-human primates. The advantage of the FSH/FSH receptor over the LHRH/LH-based vaccine lies in the fact that the former does not require an exogenous testosterone supplement to maintain accessory gland function, libido etc. The LHRH/LH-based vaccine results in azoospermia, while the FSH vaccine causes the production of low numbers of poor quality spermatozoa which are incapable of impregnating cycling females.

  19. CXCR3 Signaling Is Required for Restricted Homing of Parenteral Tuberculosis Vaccine-Induced T Cells to Both the Lung Parenchyma and Airway.

    PubMed

    Jeyanathan, Mangalakumari; Afkhami, Sam; Khera, Amandeep; Mandur, Talveer; Damjanovic, Daniela; Yao, Yushi; Lai, Rocky; Haddadi, Siamak; Dvorkin-Gheva, Anna; Jordana, Manel; Kunkel, Steven L; Xing, Zhou

    2017-10-01

    Although most novel tuberculosis (TB) vaccines are designed for delivery via the muscle or skin for enhanced protection in the lung, it has remained poorly understood whether systemic vaccine-induced memory T cells can readily home to the lung mucosa prior to and shortly after pathogen exposure. We have investigated this issue by using a model of parenteral TB immunization and intravascular immunostaining. We find that systemically induced memory T cells are restricted to the blood vessels in the lung, unable to populate either the lung parenchymal tissue or the airway under homeostatic conditions. We further find that after pulmonary TB infection, it still takes many days before such T cells can enter the lung parenchymal tissue and airway. We have identified the acquisition of CXCR3 expression by circulating T cells to be critical for their entry to these lung mucosal compartments. Our findings offer new insights into mucosal T cell biology and have important implications in vaccine strategies against pulmonary TB and other intracellular infections in the lung. Copyright © 2017 by The American Association of Immunologists, Inc.

  20. Next-generation dengue vaccines: novel strategies currently under development.

    PubMed

    Durbin, Anna P; Whitehead, Stephen S

    2011-10-01

    Dengue has become the most important arboviral infection worldwide with more than 30 million cases of dengue fever estimated to occur each year. The need for a dengue vaccine is great and several live attenuated dengue candidate vaccines are proceeding through clinical evaluation. The need to induce a balanced immune response against all four DENV serotypes with a single vaccine has been a challenge for dengue vaccine developers. A live attenuated DENV chimeric vaccine produced by Sanofi Pasteur has recently entered Phase III evaluation in numerous dengue-endemic regions of the world. Viral interference between serotypes contained in live vaccines has required up to three doses of the vaccine be given over a 12-month period of time. For this reason, novel DENV candidate vaccines are being developed with the goal of achieving a protective immune response with an immunization schedule that can be given over the course of a few months. These next-generation candidates include DNA vaccines, recombinant adenovirus vectored vaccines, alphavirus replicons, and sub-unit protein vaccines. Several of these novel candidates will be discussed.

  1. A human dendritic cell-based in vitro model to assess Mycobacterium tuberculosis SO2 vaccine immunogenicity.

    PubMed

    Etna, Marilena P; Giacomini, Elena; Severa, Martina; Pardini, Manuela; Aguilo, Nacho; Martin, Carlos; Coccia, Eliana M

    2014-01-01

    Among the tuberculosis (TB) vaccine candidates, SO2 is the prototype of the first live-attenuated vaccine that recently entered into clinical trials. To investigate the capacity of SO2 to stimulate an appropriate immune response in vitro within a human immunological context, a comparative analysis of the effects promoted by SO2, the current Bacille Calmette-Guerin (BCG) vaccine and Mycobacterium tuberculosis (Mtb) was conducted in human primary dendritic cells (DC), which are critical modulators of vaccine-induced immunity. In particular, we found that SO2 promotes the expression of maturation markers similarly to BCG but at a lower extent than Mtb. Moreover, SO2-infected DC released higher levels of interleukin (IL)-23 than BCG-infected cells, which account for the expansion of interferon (IFN)-γ-producing T cells in an IL-12-independent manner. In the autologous mixed leukocyte reaction setting, the expansion of IL-17-producing T cells was also observed in response to SO2 infection. Interestingly, apoptosis and autophagic flux, events required for the antigen presentation within MHC class II complex, were not affected in DC infected with SO2, conversely to what observed upon Mtb stimulation. Collectively, our results indicate that SO2 represents a promising TB vaccine candidate, which displays an attenuated phenotype and promotes in DC a stronger capacity to stimulate the Th response than BCG vaccine. Interestingly, the data obtained by using the human DC-based experimental setting mirrored the results derived from studies in animal models, suggesting that this system could be used for an efficient and rapid down-selection of new TB vaccine candidates, contributing to achieve the "3Rs" objective.

  2. Ensuring the optimal safety of licensed vaccines: a perspective of the vaccine research, development, and manufacturing companies.

    PubMed

    Kanesa-thasan, Niranjan; Shaw, Alan; Stoddard, Jeffrey J; Vernon, Thomas M

    2011-05-01

    Vaccine safety is increasingly a focus for the general public, health care providers, and vaccine manufacturers, because the efficacy of licensed vaccines is accepted as a given. Commitment to ensuring safety of all vaccines, including childhood vaccines, is addressed by the federal government, academia, and industry. Safety activities conducted by the vaccine research, development, and manufacturing companies occur at all stages of product development, from selection and formulation of candidate vaccines through postlicensure studies and surveillance of adverse-event reports. The contributions of multiple interacting functional groups are required to execute these tasks through the life cycle of a product. We describe here the safeguards used by vaccine manufacturers, including specific examples drawn from recent experience, and highlight some of the current challenges. Vaccine-risk communication becomes a critical area for partnership of vaccine companies with government, professional associations, and nonprofit advocacy groups to provide information on both benefits and risks of vaccines. The crucial role of the vaccine companies in ensuring the optimal vaccine-safety profile, often overlooked, will continue to grow with this dynamic arena.

  3. Understanding social context on TB cases

    NASA Astrophysics Data System (ADS)

    Ariyanto, Y.; Wati, D. M.

    2017-01-01

    Tuberculosis (TB) nowadays still becomes one of the world’s deadliest communicable disease. More than half were in South-East Asia and Western Pacific Regions, including Indonesia. As developing country, Indonesia remains classic problems in overcoming TB, that is discontinuation on treatment. Most of discontinuation on treatment among TB patients are affected by diagnostic delay that caused by patient delay. These phenomena occur in many areas, rural to suburb, coastal to plantation, and so on, and they are related with social context among community that could be social capital for each community to deal with TB. Jember as one of county in East Java is known as plantation area. It also has a high prevalence of TB. This study focused on understanding about social context among community, especially on plantation area. This cross-sectional study involved in three districts of Jember, those are Tanggul, Pakusari, and Kalisat. The data were obtained directly from the TB patients, local community, and Primary Health Care (PHC) where the patients recorded. Spatial analysis and social network analysis (SNA) were applied to obtain health seeking behavior pattern among the TB patients coincide the community. Most of TB patients had already chosen health professionals to lead the treatment, although some of them remained to choose self-medication. Meanwhile, SNA showed that religious leader was considered as main part of countermeasures of TB. But they didn’t ever become central figures. So it can be concluded that there are other parts among community who can contribute due to combatting on TB.

  4. Accelerating the development of a safe and effective HIV vaccine: HIV vaccine case study for the Decade of Vaccines.

    PubMed

    Koff, Wayne C; Russell, Nina D; Walport, Mark; Feinberg, Mark B; Shiver, John W; Karim, Salim Abdool; Walker, Bruce D; McGlynn, Margaret G; Nweneka, Chidi Victor; Nabel, Gary J

    2013-04-18

    Human immunodeficiency virus (HIV), the etiologic agent that causes AIDS, is the fourth largest killer in the world today. Despite the remarkable achievements in development of anti-retroviral therapies against HIV, and the recent advances in new prevention technologies, the rate of new HIV infections continue to outpace efforts on HIV prevention and control. Thus, the development of a safe and effective vaccine for prevention and control of AIDS remains a global public health priority and the greatest opportunity to eventually end the AIDS pandemic. Currently, there is a renaissance in HIV vaccine development, due in large part to the first demonstration of vaccine induced protection, albeit modest, in human efficacy trials, a generation of improved vaccine candidates advancing in the clinical pipeline, and newly defined targets on HIV for broadly neutralizing antibodies. The main barriers to HIV vaccine development include the global variability of HIV, lack of a validated animal model, lack of correlates of protective immunity, lack of natural protective immune responses against HIV, and the reservoir of infected cells conferred by integration of HIV's genome into the host. Some of these barriers are not unique to HIV, but generic to other variable viral pathogens such as hepatitis C and pandemic influenza. Recommendations to overcome these barriers are presented in this document, including but not limited to expansion of efforts to design immunogens capable of eliciting broadly neutralizing antibodies against HIV, expansion of clinical research capabilities to assess multiple immunogens concurrently with comprehensive immune monitoring, increased support for translational vaccine research, and engaging industry as full partners in vaccine discovery and development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Framework of behavioral indicators for outcome evaluation of TB health promotion: a Delphi study of TB suspects and Tb patients

    PubMed Central

    2014-01-01

    Background Health promotion for prevention and control of Tuberculosis (TB) is implemented worldwide because of its importance, but few reports have evaluated its impact on behavior due to a lack of standard outcome indicators. The objective of this study was to establish a framework of behavioral indicators for outcome evaluation of TB health promotion among TB suspects and patients. Methods A two-round modified Delphi method involving sixteen TB control experts was used to establish a framework of behavioral indicators for outcome evaluation of TB health promotion targeted at TB suspects and patients. Results Sixteen of seventeen invited experts in TB control (authority score of 0.91 on a 1.0 scale) participated in round 1 survey. All sixteen experts also participated in a second round survey. After two rounds of surveys and several iterations among the experts, there was consensus on a framework of indicators for measuring outcomes of TB health promotion for TB suspects and patients. For TB suspects, the experts reached consensus on 2 domains (“Healthcare seeking behavior” and “Transmission prevention”), 3 subdomains (“Seeking care after onset of TB symptoms”, “Pathways of seeking care” and “Interpersonal contact etiquette”), and 8 indicators (including among others, “Length of patient delay”). For TB patients, consensus was reached on 3 domains (“Adherence to treatment”, “Healthy lifestyle” and “Transmission prevention”), 8 subdomains (including among others, “Adherence to their medication”), and 14 indicators (including “Percentage of patients who adhered to their medication”). Operational definitions and data sources were provided for each indicator. Conclusions The findings of this study provide the basis for debate among international experts on a framework for achieving global consensus on outcome indicators for TB health promotion interventions targeted at TB patients and suspects. Such consensus will help to

  6. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine.

    PubMed

    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.

  7. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine

    PubMed Central

    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine. PMID:26435066

  8. Novel vaccine development strategies for inducing mucosal immunity

    PubMed Central

    Fujkuyama, Yoshiko; Tokuhara, Daisuke; Kataoka, Kosuke; Gilbert, Rebekah S; McGhee, Jerry R; Yuki, Yoshikazu; Kiyono, Hiroshi; Fujihashi, Kohtaro

    2012-01-01

    To develop protective immune responses against mucosal pathogens, the delivery route and adjuvants for vaccination are important. The host, however, strives to maintain mucosal homeostasis by responding to mucosal antigens with tolerance, instead of immune activation. Thus, induction of mucosal immunity through vaccination is a rather difficult task, and potent mucosal adjuvants, vectors or other special delivery systems are often used, especially in the elderly. By taking advantage of the common mucosal immune system, the targeting of mucosal dendritic cells and microfold epithelial cells may facilitate the induction of effective mucosal immunity. Thus, novel routes of immunization and antigen delivery systems also show great potential for the development of effective and safe mucosal vaccines against various pathogens. The purpose of this review is to introduce several recent approaches to induce mucosal immunity to vaccines, with an emphasis on mucosal tissue targeting, new immunization routes and delivery systems. Defining the mechanisms of mucosal vaccines is as important as their efficacy and safety, and in this article, examples of recent approaches, which will likely accelerate progress in mucosal vaccine development, are discussed. PMID:22380827

  9. Establishing Correlates of Protection for Vaccine Development: Considerations for the Respiratory Syncytial Virus Vaccine Field.

    PubMed

    Kulkarni, Prasad S; Hurwitz, Julia L; Simões, Eric A F; Piedra, Pedro A

    2018-03-01

    Correlates of protection (CoPs) can play a significant role in vaccine development by assisting the selection of vaccine candidates for clinical trials, supporting clinical trial design and implementation, and simplifying tests of vaccine modifications. Because of this important role in vaccine development, it is essential that CoPs be defined by well-designed immunogenicity and efficacy studies, with attention paid to benefits and limitations. The respiratory syncytial virus (RSV) field is unique in that a great deal of information about the humoral response is available from basic research and clinical studies. Polyclonal and monoclonal antibodies have been used routinely in the clinic to protect vulnerable infants from infection, providing a wealth of information about correlations between neutralizing antibodies and disease prevention. Considerations for the establishment of future CoPs to support RSV vaccine development in different populations are therefore discussed.

  10. Challenges and opportunities for meningococcal vaccination in the developing world.

    PubMed

    Shaker, Rouba; Fayad, Danielle; Dbaibo, Ghassan

    2018-05-04

    Meningococcal disease continues to be a life threatening infection with high morbidity and mortality even in appropriately treated patients. Meningococcal vaccination plays a major role in the control of the disease; however, implementing vaccination remains problematic in the developing world. The objective of this review is to identify the challenges facing the use of meningococcal vaccines in the developing world in order to discuss the opportunities and available solutions to improve immunization in these countries. Inadequate epidemiologic information necessary to implement vaccination and financial challenges predominate. Multiple measures are needed to achieve the successful implementation of meningococcal conjugate vaccination programs that protect against circulating serogroups in developing countries including enhanced surveillance systems, financial support and aid through grants, product development partnerships that are the end result of effective collaboration and communication between different interdependent stakeholders to develop affordable vaccines, and demonstration of the cost-effectiveness of new meningococcal vaccines.

  11. Developing vaccines to counter bioterrorist threats.

    PubMed

    Altmann, Daniel M

    2005-06-01

    Large and innovative research programs are underway to define the immune parameters for vaccines against a wide array of pathogens considered to represent a potential bioterrorist threat. However, the development and utilization of such vaccines presents a number of predicaments that have not previously been addressed by the field of vaccinology.

  12. Development of Peptide Vaccines in Dengue.

    PubMed

    Reginald, Kavita; Chan, Yanqi; Plebanski, Magdalena; Poh, Chit Laa

    2017-09-13

    Dengue is one of the most important arboviral infection worldwide, infecting up to 390 million people and causing 25,000 deaths annually. Although a licensed dengue vaccine is available, it is not efficacious against dengue serotypes that infect people living in South East Asia, where dengue is an endemic disease. Hence, there is an urgent need to develop an efficient dengue vaccine for this region. Data from different clinical trials indicate that a successful dengue vaccine must elicit both neutralizing antibodies and cell mediated immunity. This can be achieved by designing a multi-epitope peptide vaccine comprising B, CD8+ and CD4+ T cell epitopes. As recognition of T cell epitopes are restricted by human leukocyte antigens (HLA), T cell epitopes which are able to recognize several major HLAs will be preferentially included in the vaccine design. While peptide vaccines are safe, biocompatible and cost-effective, it is poorly immunogenic. Strategies to improve its immunogenicity by the use of long peptides, adjuvants and nanoparticle delivery mechanisms are discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Hit Generation in TB Drug Discovery: From Genome to Granuloma

    PubMed Central

    2018-01-01

    Current tuberculosis (TB) drug development efforts are not sufficient to end the global TB epidemic. Recent efforts have focused on the development of whole-cell screening assays because biochemical, target-based inhibitor screens during the last two decades have not delivered new TB drugs. Mycobacterium tuberculosis (Mtb), the causative agent of TB, encounters diverse microenvironments and can be found in a variety of metabolic states in the human host. Due to the complexity and heterogeneity of Mtb infection, no single model can fully recapitulate the in vivo conditions in which Mtb is found in TB patients, and there is no single “standard” screening condition to generate hit compounds for TB drug development. However, current screening assays have become more sophisticated as researchers attempt to mirror the complexity of TB disease in the laboratory. In this review, we describe efforts using surrogates and engineered strains of Mtb to focus screens on specific targets. We explain model culture systems ranging from carbon starvation to hypoxia, and combinations thereof, designed to represent the microenvironment which Mtb encounters in the human body. We outline ongoing efforts to model Mtb infection in the lung granuloma. We assess these different models, their ability to generate hit compounds, and needs for further TB drug development, to provide direction for future TB drug discovery. PMID:29384369

  14. TB control programmes: the challenges for Africa.

    PubMed

    Harries, T

    1996-11-01

    Governmental neglect of tuberculosis (TB), inadequately managed and inaccurately designed TB control programs, population growth, and the HIV epidemic account for the resurgence of TB in sub-Saharan Africa. The World Health Organization and the International Union against TB and Lung Disease have developed a TB control strategy that aims to reduce mortality, morbidity, and transmission of TB. It aims for an 85% cure rate among detected new cases of smear-positive TB and a 70% rate of detecting existing smear-positive TB cases. The strategy involves the provision of short-course chemotherapy (SCC) to all identified smear-positive TB cases through directly observed treatment (DOTS). SCC treatment regimens for smear-positive pulmonary TB recommended for sub-Saharan African countries are: initial phase = daily administration over 2 months of streptomycin, rifampicin, isoniazid, and pyrazinamide; continuation phase = 3 doses over 4 months of isoniazid and rifampicin or daily administration of thiacetazone and isoniazid or of ethambutol and isoniazid. A TB control policy must be implemented to bring about effective TB control. The essential elements of this policy include political commitment, case detection through passive case-finding, SCC, a regular supply of essential drugs, and a monitoring and evaluation system. Political commitment involves establishing a National TB Control Program to be integrated into the existing health structure. Increased awareness of TB in the community and among health workers and a reference laboratory are needed to make case finding successful. A distribution and logistics system is needed to ensure uninterrupted intake of drugs throughout treatment. These regimens have been very successful and cost-effective but pose several disadvantages (e.g., heavy workload of recommended 3 sputum smear tests). A simplified approach involves 1 initial sputum smear for 6 months; 6-months, intermittent rifampicin-based therapy, 100% DOTS throughout

  15. Vesicular Stomatitis Virus-Vectored Multi-Antigen Tuberculosis Vaccine Limits Bacterial Proliferation in Mice following a Single Intranasal Dose

    PubMed Central

    Zhang, Ming; Dong, Chunsheng; Xiong, Sidong

    2017-01-01

    Tuberculosis (TB) remains a serious health problem worldwide, and an urgent need exists to improve or replace the available vaccine, Mycobacterium bovis bacillus Calmette-Guérin (BCG). Most vaccination protocols adapt two or three doses to induce long-term lasting immunity. Our previous study showed that the naked DNA encoding the triple-antigen fusion TFP846 (Rv3615c-Mtb10.4-Rv2660c) induced robust T cellular immune responses accompanying four inoculations against mycobacteria infection. However, a number of compliance issues exist in some areas lacking the appropriate medical infrastructure with multiple administrations. In this study, a novel vesicular stomatitis virus expressing TFP846 (VSV-846) was developed and the immune responses elicited by VSV-846 were evaluated. We observed that intranasal delivery of VSV-846 induced a potent antigen-specific T cell response following a single dose and VSV-846 efficiently controlled bacterial growth to levels ~10-fold lower than that observed in the mock group 6 weeks post-infection in BCG-infected mice. Importantly, mice immunized with VSV-846 provided long-term protection against mycobacteria infection compared with those receiving p846 or BCG immunization. Increased memory T cells were also observed in the spleens of VSV-846-vaccinated mice, which could be a potential mechanism associated with long-term protective immune response. These findings supported the use of VSV as an antigen delivery vector with the potential for TB vaccine development. PMID:28224119

  16. Progress in Developing Virus-like Particle Influenza Vaccines

    PubMed Central

    Quan, Fu-Shi; Lee, Young-Tae; Kim, Ki-Hye; Kim, Min-Chul; Kang, Sang-Moo

    2016-01-01

    Summary Recombinant vaccines based on virus-like particles (VLPs) or nanoparticles have been successful in their safety and efficacy in preclinical and clinical studies. The technology of expressing enveloped VLP vaccines has combined with molecular engineering of proteins in membrane-anchor and immunogenic forms mimicking the native conformation of surface proteins on the enveloped viruses. This review summarizes recent developments in influenza VLP vaccines against seasonal, pandemic, and avian influenza viruses from the perspective of use in humans. The immunogenicity and efficacies of influenza VLP vaccine in the homologous and cross-protection were reviewed. Discussions include limitations of current influenza vaccination strategies and future directions to confer broadly cross protective new influenza vaccines as well as vaccination. PMID:27058302

  17. Varicella and herpes zoster vaccine development: lessons learned

    PubMed Central

    Warren-Gash, Charlotte; Forbes, Harriet; Breuer, Judith

    2017-01-01

    ABSTRACT Introduction: Before vaccination, varicella zoster virus (VZV), which is endemic worldwide, led to almost universal infection. This neurotropic virus persists lifelong by establishing latency in sensory ganglia, where its reactivation is controlled by VZV-specific T-cell immunity. Lifetime risk of VZV reactivation (zoster) is around 30%. Vaccine development was galvanised by the economic and societal burden of VZV, including debilitating zoster complications that largely affect older individuals. Areas covered: We describe the story of development, licensing and implementation of live attenuated vaccines against varicella and zoster. We consider the complex backdrop of VZV virology, pathogenesis and immune responses in the absence of suitable animal models and examine the changing epidemiology of VZV disease. We review the vaccines’ efficacy, safety, effectiveness and coverage using evidence from trials, observational studies from large routine health datasets and clinical post-marketing surveillance studies and outline newer developments in subunit and inactivated vaccines. Expert commentary: Safe and effective, varicella and zoster vaccines have already made major inroads into reducing the burden of VZV disease globally. As these live vaccines have the potential to reactivate and cause clinical disease, developing alternatives that do not establish latency is an attractive prospect but will require better understanding of latency mechanisms. PMID:29047317

  18. A world of cities and the end of TB.

    PubMed

    Prasad, Amit; Ross, Alex; Rosenberg, Paul; Dye, Christopher

    2016-03-01

    The WHO's End TB Strategy aims to reduce TB deaths by 95% and incidence by 90% between 2015 and 2035. As the world rapidly urbanizes, more people could have access to better infrastructure and services to help combat poverty and infectious diseases, including TB. And yet large numbers of people now live in overcrowded slums, with poor access to urban health services, amplifying the burden of TB. An alignment of the Sustainable Development Goals (SDGs) for health and for urban development provides an opportunity to accelerate the overall decline in infection and disease, and to create cities free of TB. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

  19. Development of Burkholderia mallei and pseudomallei vaccines.

    PubMed

    Silva, Ediane B; Dow, Steven W

    2013-01-01

    Burkholderia mallei and Burkholderia pseudomallei are Gram-negative bacteria that cause glanders and melioidosis, respectively. Inhalational infection with either organism can result in severe and rapidly fatal pneumonia. Inoculation by the oral and cutaneous routes can also produce infection. Chronic infection may develop after recovery from acute infection with both agents, and control of infection with antibiotics requires prolonged treatment. Symptoms for both meliodosis and glanders are non-specific, making diagnosis difficult. B. pseudomallei can be located in the environment, but in the host, B. mallei and B. psedomallei are intracellular organisms, and infection results in similar immune responses to both agents. Effective early innate immune responses are critical to controlling the early phase of the infection. Innate immune signaling molecules such as TLR, NOD, MyD88, and pro-inflammatory cytokines such as IFN-γ and TNF-α play key roles in regulating control of infection. Neutrophils and monocytes are critical cells in the early infection for both microorganisms. Both monocytes and macrophages are necessary for limiting dissemination of B. pseudomallei. In contrast, the role of adaptive immune responses in controlling Burkholderia infection is less well understood. However, T cell responses are critical for vaccine protection from Burkholderia infection. At present, effective vaccines for prevention of glanders or meliodosis have not been developed, although recently development of Burkholderia vaccines has received renewed attention. This review will summarize current and past approaches to develop B. mallei and B. pseudomalllei vaccines, with emphasis on immune mechanisms of protection and the challenges facing the field. At present, immunization with live attenuated bacteria provides the most effective and durable immunity, and it is important therefore to understand the immune correlates of protection induced by live attenuated vaccines. Subunit

  20. Development of Burkholderia mallei and pseudomallei vaccines

    PubMed Central

    Silva, Ediane B.; Dow, Steven W.

    2013-01-01

    Burkholderia mallei and Burkholderia pseudomallei are Gram-negative bacteria that cause glanders and melioidosis, respectively. Inhalational infection with either organism can result in severe and rapidly fatal pneumonia. Inoculation by the oral and cutaneous routes can also produce infection. Chronic infection may develop after recovery from acute infection with both agents, and control of infection with antibiotics requires prolonged treatment. Symptoms for both meliodosis and glanders are non-specific, making diagnosis difficult. B. pseudomallei can be located in the environment, but in the host, B. mallei and B. psedomallei are intracellular organisms, and infection results in similar immune responses to both agents. Effective early innate immune responses are critical to controlling the early phase of the infection. Innate immune signaling molecules such as TLR, NOD, MyD88, and pro-inflammatory cytokines such as IFN-γ and TNF-α play key roles in regulating control of infection. Neutrophils and monocytes are critical cells in the early infection for both microorganisms. Both monocytes and macrophages are necessary for limiting dissemination of B. pseudomallei. In contrast, the role of adaptive immune responses in controlling Burkholderia infection is less well understood. However, T cell responses are critical for vaccine protection from Burkholderia infection. At present, effective vaccines for prevention of glanders or meliodosis have not been developed, although recently development of Burkholderia vaccines has received renewed attention. This review will summarize current and past approaches to develop B. mallei and B. pseudomalllei vaccines, with emphasis on immune mechanisms of protection and the challenges facing the field. At present, immunization with live attenuated bacteria provides the most effective and durable immunity, and it is important therefore to understand the immune correlates of protection induced by live attenuated vaccines. Subunit

  1. TIME Impact - a new user-friendly tuberculosis (TB) model to inform TB policy decisions.

    PubMed

    Houben, R M G J; Lalli, M; Sumner, T; Hamilton, M; Pedrazzoli, D; Bonsu, F; Hippner, P; Pillay, Y; Kimerling, M; Ahmedov, S; Pretorius, C; White, R G

    2016-03-24

    Tuberculosis (TB) is the leading cause of death from infectious disease worldwide, predominantly affecting low- and middle-income countries (LMICs), where resources are limited. As such, countries need to be able to choose the most efficient interventions for their respective setting. Mathematical models can be valuable tools to inform rational policy decisions and improve resource allocation, but are often unavailable or inaccessible for LMICs, particularly in TB. We developed TIME Impact, a user-friendly TB model that enables local capacity building and strengthens country-specific policy discussions to inform support funding applications at the (sub-)national level (e.g. Ministry of Finance) or to international donors (e.g. the Global Fund to Fight AIDS, Tuberculosis and Malaria).TIME Impact is an epidemiological transmission model nested in TIME, a set of TB modelling tools available for free download within the widely-used Spectrum software. The TIME Impact model reflects key aspects of the natural history of TB, with additional structure for HIV/ART, drug resistance, treatment history and age. TIME Impact enables national TB programmes (NTPs) and other TB policymakers to better understand their own TB epidemic, plan their response, apply for funding and evaluate the implementation of the response.The explicit aim of TIME Impact's user-friendly interface is to enable training of local and international TB experts towards independent use. During application of TIME Impact, close involvement of the NTPs and other local partners also builds critical understanding of the modelling methods, assumptions and limitations inherent to modelling. This is essential to generate broad country-level ownership of the modelling data inputs and results. In turn, it stimulates discussions and a review of the current evidence and assumptions, strengthening the decision-making process in general.TIME Impact has been effectively applied in a variety of settings. In South Africa, it

  2. Novel immunotherapy vaccine development.

    PubMed

    Jutel, Marek; Akdis, Cezmi A

    2014-12-01

    Allergen-specific immunotherapy is the only curative treatment for allergic diseases. In spite of the great progress in both vaccine development and the methods of allergen immunotherapy (AIT) in recent years, several key problems related to limited efficacy, side-effects, low patient adherence and the relatively high costs due to the long duration (3-5 years) remain to be solved. The current approaches aiming at optimization of AIT are reviewed, including both conceptual studies in experimental models and proof-of-concept - as well as large, multicenter clinical studies. The most promising approaches to improve efficacy and safety of vaccine-based AIT include bypassing IgE binding and targeting allergen-specific T cells using hypoallergenic recombinant allergen derivatives and immunogenic peptides, the use of new adjuvants and stimulators of the innate immune response, the fusion of allergens to immune modifiers and peptide carrier proteins and new routes of vaccine administration. The cloning of allergen proteins and genetic engineering enabled the production of vaccines that have well defined molecular, immunologic and biologic characteristics as well as modified molecular structure. These new compounds along with new immunization protocols can bring us closer to the ultimate goal of AIT, that is, complete cure of a large number of allergic patients.

  3. Testing for TB Infection

    MedlinePlus

    ... Search Form Controls Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  4. Extensively Drug-Resistant Tuberculosis (XDR TB)

    MedlinePlus

    ... TB Reference Laboratory Network, the National TB Surveillance System in the United States, the national reference laboratory of South Korea, and ... capacity in the U.S. and abroad; and Developing education, risk, and media communications ... – United States, 1993–2006 CDC. CDC’s Role in Preventing XDR ...

  5. Status of vaccine research and development for Shigella.

    PubMed

    Mani, Sachin; Wierzba, Thomas; Walker, Richard I

    2016-06-03

    Shigella are gram-negative bacteria that cause severe diarrhea and dysentery. In 2013, Shigella infections caused an estimated 34,400 deaths in children less than five years old and, in 2010, an estimated 40,000 deaths in persons older than five years globally. New disease burden estimates from newly deployed molecular diagnostic assays with increased sensitivity suggest that Shigella-associated morbidity may be much greater than previous disease estimates from culture-based methods. Primary prevention of this disease should be based on universal provision of potable water and sanitation methods and improved personal and food hygiene. However, an efficacious and low-cost vaccine would complement and accelerate disease reduction while waiting for universal access to water, sanitation, and hygiene improvements. This review article provides a landscape of Shigella vaccine development efforts. No vaccine is yet available, but human and animal challenge-rechallenge trials with virulent Shigella as well as observational studies in Shigella-endemic areas have shown that the incidence of disease decreases following Shigella infection, pointing to biological feasibility of a vaccine. Immunity to Shigella appears to be strain-specific, so a vaccine that covers the most commonly detected strains (i.e., S. flexneri 2a, 3a, 6, and S. sonnei) or a vaccine using cross-species conserved antigens would likely be most effective. Vaccine development and testing may be accelerated by use of animal models, such as the guinea pig keratoconjunctivitis or murine pneumonia models. Because there is no correlate of protection, however, human studies will be necessary to evaluate vaccine efficacy prior to deployment. A diversity of Shigella vaccine constructs are under development, including live attenuated, formalin-killed whole-cell, glycoconjugate, subunit, and novel antigen vaccines (e.g., Type III secretion system and outer membrane proteins). Copyright © 2016 World Health Organization

  6. Large animal models for vaccine development and testing.

    PubMed

    Gerdts, Volker; Wilson, Heather L; Meurens, Francois; van Drunen Littel-van den Hurk, Sylvia; Wilson, Don; Walker, Stewart; Wheler, Colette; Townsend, Hugh; Potter, Andrew A

    2015-01-01

    The development of human vaccines continues to rely on the use of animals for research. Regulatory authorities require novel vaccine candidates to undergo preclinical assessment in animal models before being permitted to enter the clinical phase in human subjects. Substantial progress has been made in recent years in reducing and replacing the number of animals used for preclinical vaccine research through the use of bioinformatics and computational biology to design new vaccine candidates. However, the ultimate goal of a new vaccine is to instruct the immune system to elicit an effective immune response against the pathogen of interest, and no alternatives to live animal use currently exist for evaluation of this response. Studies identifying the mechanisms of immune protection; determining the optimal route and formulation of vaccines; establishing the duration and onset of immunity, as well as the safety and efficacy of new vaccines, must be performed in a living system. Importantly, no single animal model provides all the information required for advancing a new vaccine through the preclinical stage, and research over the last two decades has highlighted that large animals more accurately predict vaccine outcome in humans than do other models. Here we review the advantages and disadvantages of large animal models for human vaccine development and demonstrate that much of the success in bringing a new vaccine to market depends on choosing the most appropriate animal model for preclinical testing. © The Author 2015. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. Consensus on the Development of Vaccines against Naturally Acquired Melioidosis

    PubMed Central

    Funnell, Simon G.P.; Torres, Alfredo G.; Morici, Lisa A.; Brett, Paul J.; Dunachie, Susanna; Atkins, Timothy; Altmann, Daniel M.; Bancroft, Gregory; Peacock, Sharon J.

    2015-01-01

    Several candidates for a vaccine against Burkholderia pseudomallei, the causal bacterium of melioidosis, have been developed, and a rational approach is now needed to select and advance candidates for testing in relevant nonhuman primate models and in human clinical trials. Development of such a vaccine was the topic of a meeting in the United Kingdom in March 2014 attended by international candidate vaccine developers, researchers, and government health officials. The focus of the meeting was advancement of vaccines for prevention of natural infection, rather than for protection from the organism’s known potential for use as a biological weapon. A direct comparison of candidate vaccines in well-characterized mouse models was proposed. Knowledge gaps requiring further research were identified. Recommendations were made to accelerate the development of an effective vaccine against melioidosis. PMID:25992835

  8. Tuberculosis elimination in the post Millennium Development Goals era.

    PubMed

    Wejse, Christian

    2015-03-01

    The Millennium Development Goal for tuberculosis (TB) is to stop the increase in incidence and halve the mortality of TB between 1990 and 2015. This goal has now been reached on a global scale, although not in the most affected region of Africa. The new target is TB elimination, defined as one case of active TB per one million population per year, which is to be reached before 2050. This review will discuss the main tools in play, namely case-finding and new diagnostics, increased access and effectiveness of anti-TB therapy (directly observed therapy, short course (DOTS)), preventive therapy for latent infection, and vaccination. Each approach is discussed and a way forward in research and management is suggested. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

  9. Prospects for the development of fungal vaccines.

    PubMed

    Deepe, G S

    1997-10-01

    In an era that emphasizes the term "cost-effective," vaccines are the ideal solution to preventing disease at a relatively low cost to society. Much of the previous emphasis has been on childhood scourges such as measles, mumps, rubella, poliomyelitis, and Haemophilus influenzae type b. The concept of vaccines for fungal diseases has had less impact because of the perceived limited problem. However, fungal diseases have become increasingly appreciated as serious medical problems that require recognition and aggressive management. The escalation in the incidence and prevalence of infection has prompted a renewed interest in vaccine development. Herein, I discuss the most recent developments in the search for vaccines to combat fungal infections. Investigators have discovered several inert substances from various fungi that can mediate protection in animal models. The next challenge will be to find the suitable mode of delivery for these immunogens.

  10. [Approaches and problems in vaccine development against leishmaniasis].

    PubMed

    Allahverdiyev, Adil; Bağirova, Melahat; Cakir Koç, Rabia; Oztel, Olga Nehir; Elçıçek, Serhat; Ateş, Sezen Canım; Karaca, Tuğçe Deniz

    2010-01-01

    Leishmaniasis is a major public health problem of the world and Turkey. Recently there has been increasing interest in vaccine studies among strategies for control of leishmaniasis. Recently the increase of interest in vaccine studies among leishmaniasis control strategies makes the subject more up to date. So the aim of this review is to present information about recent vaccine studies, problems and new strategies for vaccine development studies. There are 3 generations of vaccine against leishmaniasis. First-generation vaccines are killed or live attenuated parasites; second-generation vaccines are recombinant or native antigens and live genetically modified parasites (knock out and suicidal cassettes), third generation vaccines are DNA vaccines. Also vector salivary proteins, dendritic cells and non-pathogenic L. tarentolae have been used as vaccine candidates. However there is still no effective vaccine against leishmaniasis. Since polymer conjugates considerably increase immunogenicity, polymer based vaccine studies have gained importance in recent years. However, there has not been such a study for an antileishmanial vaccine yet. LPG, surface antigen of Leishmania promastigotes, and polymer conjugates may be promising in antileishmanial vaccine studies so we are carrying out a TUBITAK Project on this subject which has been given the number, 1085170SBAG-4007.

  11. HIV vaccine development: past, present and future.

    PubMed

    Robb, Merlin L

    2010-12-01

    The search for an HIV vaccine began following the discovery of the virus more than 25 years ago. Despite important progress, an effective vaccine remains an elusive goal that will likely require many more years of R&D to achieve. Following recent advances in research, however, there has been increased optimism that a prophylactic HIV vaccine is feasible. A consensus is forming among researchers to support a larger role for proof-of-concept efficacy clinical trials, conducted in parallel with invigorated basic research efforts and testing in animal models, to accelerate the discovery of key principles that will guide rational vaccine development.

  12. Safety and efficacy of the C-Tb skin test to diagnose Mycobacterium tuberculosis infection, compared with an interferon γ release assay and the tuberculin skin test: a phase 3, double-blind, randomised, controlled trial.

    PubMed

    Ruhwald, Morten; Aggerbeck, Henrik; Gallardo, Rafael Vázquez; Hoff, Søren T; Villate, José I; Borregaard, Bettine; Martinez, José A; Kromann, Ingrid; Penas, Antón; Anibarro, Luis L; de Souza-Galvão, Maria Luiza; Sánchez, Francisca; Rodrigo-Pendás, Jose Ángel; Noguera-Julian, Antoni; Martínez-Lacasa, Xavier; Tuñez, Maria Victoria; Fernández, Virginia Leiro; Millet, Joan P; Moreno, Antonio; Cobos, Nazaret; Miró, José M; Roldan, Llanos; Orcau, Angels; Andersen, Peter; Caylá, Joan A

    2017-04-01

    Targeted screening and treatment of Mycobacterium tuberculosis infection substantially reduces the risk of developing active tuberculosis. C-Tb (Statens Serum Institute, Copenhagen, Denmark) is a novel specific skin test based on ESAT-6 and CFP10 antigens. We investigated the safety and diagnostic potential of C-Tb compared with established tests in the contact-tracing setting. Negative controls, close contacts, occasional contacts, and patients with active pulmonary tuberculosis were enrolled at 13 centres in Spain. We compared C-Tb with the QuantiFERON-TB Gold In-Tube ([QFT] Qiagen, Hilden, Germany) interferon γ release assay (IGRA) and the purified protein derivative (PPD) RT 23 tuberculin skin test ([TST] Statens Serum Institute). All participants older than 5 years were tested with QFT. Some participants in the negative control group received C-Tb without the TST to test for potential interactions between C-Tb and PPD RT 23. The rest were randomly assigned in blocks of ten and tested with both C-Tb and TST, with five in each block receiving injection of C-Tb in the right arm and the TST in the left arm and five vice versa. The primary and safety analyses were done in all participants randomly assigned to a group who received any test. This trial is registered with ClinicalTrials.gov, number NCT01631266, and with EudraCT, number 2011-005617-36. From July 24, 2012, to Oct 2, 2014, 979 participants were enrolled, of whom 263 were negative controls, 299 were occasional contacts, 316 were close contacts, and 101 were patients with tuberculosis. 970 (99%) participants completed the trial. Induration sizes were similar for C-Tb and TST, but TST positivity was affected by BCG vaccination status. We found a strong positive trend towards C-Tb test positivity with increasing risk of infection, from 3% in negative controls to 16% in occasional contacts, to 43% in close contacts. C-Tb and QFT results were concordant in 785 (94%) of 834 participants aged 5 years and older

  13. Milestones in contraceptive vaccines development and hurdles in their application

    PubMed Central

    Gupta, Satish Kumar; Shrestha, Abhinav; Minhas, Vidisha

    2014-01-01

    Contraceptive vaccines have been proposed for controlling the growing human population and wildlife population management. Multiple targets such as gonadotropin releasing hormone (GnRH), luteinizing hormone, follicle stimulating hormone, gonadotropin receptors, sperm-specific proteins and zona pellucida glycoproteins have been exploited to develop contraceptive vaccine and their efficacy investigated and shown in various experimental animal models. Vaccines based on GnRH have found application in immuno-castration of male pigs for prevention of boar-taint. Vaccines based on zona pellucida glycoproteins have shown promising results for population management of wild horses and white-tailed deer. Phase II clinical trials in women with β-human chorionic gonadotropin (β-hCG)-based contraceptive vaccine established proof of principle that these can be developed for human application. Block in fertility by β-hCG contraceptive vaccine was reversible. Further research inputs are required to establish the safety of contraceptive vaccines, improve their immunogenicity and to develop novel vaccine delivery platforms for providing long lasting immunity. PMID:24262991

  14. Newcastle Disease Virus as a Vaccine Vector for Development of Human and Veterinary Vaccines

    PubMed Central

    Kim, Shin-Hee; Samal, Siba K.

    2016-01-01

    Viral vaccine vectors have shown to be effective in inducing a robust immune response against the vaccine antigen. Newcastle disease virus (NDV), an avian paramyxovirus, is a promising vaccine vector against human and veterinary pathogens. Avirulent NDV strains LaSota and B1 have long track records of safety and efficacy. Therefore, use of these strains as vaccine vectors is highly safe in avian and non-avian species. NDV replicates efficiently in the respiratory track of the host and induces strong local and systemic immune responses against the foreign antigen. As a vaccine vector, NDV can accommodate foreign sequences with a good degree of stability and as a RNA virus, there is limited possibility for recombination with host cell DNA. Using NDV as a vaccine vector in humans offers several advantages over other viral vaccine vectors. NDV is safe in humans due to host range restriction and there is no pre-existing antibody to NDV in the human population. NDV is antigenically distinct from common human pathogens. NDV replicates to high titer in a cell line acceptable for human vaccine development. Therefore, NDV is an attractive vaccine vector for human pathogens for which vaccines are currently not available. NDV is also an attractive vaccine vector for animal pathogens. PMID:27384578

  15. Newcastle Disease Virus as a Vaccine Vector for Development of Human and Veterinary Vaccines.

    PubMed

    Kim, Shin-Hee; Samal, Siba K

    2016-07-04

    Viral vaccine vectors have shown to be effective in inducing a robust immune response against the vaccine antigen. Newcastle disease virus (NDV), an avian paramyxovirus, is a promising vaccine vector against human and veterinary pathogens. Avirulent NDV strains LaSota and B1 have long track records of safety and efficacy. Therefore, use of these strains as vaccine vectors is highly safe in avian and non-avian species. NDV replicates efficiently in the respiratory track of the host and induces strong local and systemic immune responses against the foreign antigen. As a vaccine vector, NDV can accommodate foreign sequences with a good degree of stability and as a RNA virus, there is limited possibility for recombination with host cell DNA. Using NDV as a vaccine vector in humans offers several advantages over other viral vaccine vectors. NDV is safe in humans due to host range restriction and there is no pre-existing antibody to NDV in the human population. NDV is antigenically distinct from common human pathogens. NDV replicates to high titer in a cell line acceptable for human vaccine development. Therefore, NDV is an attractive vaccine vector for human pathogens for which vaccines are currently not available. NDV is also an attractive vaccine vector for animal pathogens.

  16. Workshop report: Malaria vaccine development in Europe--preparing for the future.

    PubMed

    Viebig, Nicola K; D'Alessio, Flavia; Draper, Simon J; Sim, B Kim Lee; Mordmüller, Benjamin; Bowyer, Paul W; Luty, Adrian J F; Jungbluth, Stefan; Chitnis, Chetan E; Hill, Adrian V S; Kremsner, Peter; Craig, Alister G; Kocken, Clemens H M; Leroy, Odile

    2015-11-17

    The deployment of a safe and effective malaria vaccine will be an important tool for the control of malaria and the reduction in malaria deaths. With the launch of the 2030 Malaria Vaccine Technology Roadmap, the malaria community has updated the goals and priorities for the development of such a vaccine and is now paving the way for a second phase of malaria vaccine development. During a workshop in Brussels in November 2014, hosted by the European Vaccine Initiative, key players from the European, North American and African malaria vaccine community discussed European strategies for future malaria vaccine development in the global context. The recommendations of the European malaria community should guide researchers, policy makers and funders of global health research and development in fulfilling the ambitious goals set in the updated Malaria Vaccine Technology Roadmap. Copyright © 2015.

  17. Progress in HIV vaccine development

    PubMed Central

    Hsu, Denise C.; O'Connell, Robert J.

    2017-01-01

    ABSTRACT An HIV-1 vaccine is needed to curtail the HIV epidemic. Only one (RV144) out of the 6 HIV-1 vaccine efficacy trials performed showed efficacy. A potential mechanism of protection is the induction of functional antibodies to V1V2 region of HIV envelope. The 2 main current approaches to the generation of protective immunity are through broadly neutralizing antibodies (bnAb) and induction of functional antibodies (non-neutralizing Abs with other potential anti-viral functions). Passive immunization using bnAb has advanced into phase II clinical trials. The induction of bnAb using mimics of the natural Env trimer or B-cell lineage vaccine design is still in pre-clinical phase. An attempt at optimization of protective functional antibodies will be assessed next with the efficacy trial (HVTN702) about to start. With on-going optimization of prime/boost strategies, the development of mosaic immunogens, replication competent vectors, and emergence of new strategies designed to induce bnAb, the prospects for a preventive HIV vaccine have never been more promising. PMID:28281871

  18. MALVAC 2012 scientific forum: accelerating development of second-generation malaria vaccines

    PubMed Central

    2012-01-01

    The World Health Organization (WHO) convened a malaria vaccines committee (MALVAC) scientific forum from 20 to 21 February 2012 in Geneva, Switzerland, to review the global malaria vaccine portfolio, to gain consensus on approaches to accelerate second-generation malaria vaccine development, and to discuss the need to update the vision and strategic goal of the Malaria Vaccine Technology Roadmap. This article summarizes the forum, which included reviews of leading Plasmodium falciparum vaccine candidates for pre-erythrocytic vaccines, blood-stage vaccines, and transmission-blocking vaccines. Other major topics included vaccine candidates against Plasmodium vivax, clinical trial site capacity development in Africa, trial design considerations for a second-generation malaria vaccine, adjuvant selection, and regulatory oversight functions including vaccine licensure. PMID:23140365

  19. Current Trends in West Nile Virus Vaccine Development

    PubMed Central

    Amanna, Ian J.; Slifka, Mark K.

    2014-01-01

    West Nile virus (WNV) is a mosquito-borne flavivirus that has become endemic in the United States. From 1999-2012, there have been 37,088 reported cases of WNV and 1,549 deaths, resulting in a 4.2% case-fatality rate. Despite development of effective WNV vaccines for horses, there is no vaccine to prevent human WNV infection. Several vaccines have been tested in preclinical studies and to date there have been 8 clinical trials, with promising results in terms of safety and induction of antiviral immunity. Although mass vaccination is unlikely to be cost-effective, implementation of a targeted vaccine program may be feasible if a safe and effective vaccine can be brought to market. Further evaluation of new and advanced vaccine candidates is strongly encouraged. PMID:24689659

  20. Novel Platforms for the Development of a Universal Influenza Vaccine

    PubMed Central

    Kumar, Arun; Meldgaard, Trine Sundebo; Bertholet, Sylvie

    2018-01-01

    Despite advancements in immunotherapeutic approaches, influenza continues to cause severe illness, particularly among immunocompromised individuals, young children, and elderly adults. Vaccination is the most effective way to reduce rates of morbidity and mortality caused by influenza viruses. Frequent genetic shift and drift among influenza-virus strains with the resultant disparity between circulating and vaccine virus strains limits the effectiveness of the available conventional influenza vaccines. One approach to overcome this limitation is to develop a universal influenza vaccine that could provide protection against all subtypes of influenza viruses. Moreover, the development of a novel or improved universal influenza vaccines may be greatly facilitated by new technologies including virus-like particles, T-cell-inducing peptides and recombinant proteins, synthetic viruses, broadly neutralizing antibodies, and nucleic acid-based vaccines. This review discusses recent scientific advances in the development of next-generation universal influenza vaccines. PMID:29628926

  1. Veterinary vaccines and their use in developing countries.

    PubMed

    Lubroth, J; Rweyemamu, M M; Viljoen, G; Diallo, A; Dungu, B; Amanfu, W

    2007-04-01

    The burden of infectious diseases in livestock and other animals continues to be a major constraint to sustained agricultural development, food security, and participation of developing and in-transition countries in the economic benefits of international trade in livestock commodities. Targeted measures must be instituted in those countries to reduce the occurrence of infectious diseases. Quality veterinary vaccines used strategically can and should be part of government sanctioned-programmes. Vaccination campaigns must be part of comprehensive disease control programmes, which, in the case of transboundary animal diseases, require a regional approach if they are to be successful. This paper focuses on the salient transboundary animal diseases and examines current vaccine use, promising vaccine research, innovative technologies that can be applied in countries in some important developing regions of the world, and the role of public/private partnerships.

  2. Tuberculosis Facts - Exposure to TB

    MedlinePlus

    Tuberculosis (TB) Facts Exposure to TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination

  3. Tuberculosis Facts - Testing for TB

    MedlinePlus

    Tuberculosis (TB) Facts Testing for TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination

  4. [Dengue, zika, chikungunya and the development of vaccines].

    PubMed

    Kantor, Isabel N

    2018-01-01

    Dengue (DENV), zika (ZIKV) and chikungunya (CHIKV), three arbovirosis transmitted by Aedes mosquitoes, have spread in recent decades in humid tropical and subtropical zones. Dengue is epidemic in subtropical areas of Argentina. DENV infection confers lasting immunity against the infecting serotype but increases the risk of serious disease upon reinfection by any of the other three. The recombinant tetravalent vaccine Dengvaxia® prevents severe dengue and hospitalization in seropositive subjects. In 2017, Dengvaxia was approved in Argentina, for ages 9 to 45, but is not included in the national vaccination calendar. Two other vaccines are in Phase III evaluation: one developed by NIAID / Instituto Butantan and the other by Takeda. ZIKV, a virus associated with microcephaly in newborns in Brazil, circulates since 2016 in Argentina. There is still not effective treatment nor vaccine with proven activity against ZIKV. There has been no active circulation of CHIKV in Argentina in 2017. Outbreaks of CHIKV fever have a complication: the development of chronic post-disease rheumatism. There are not approved vaccines for humans nor effective antiviral therapies. The seriousness of these virosis has contributed to a rapid progress in the knowledge of the infection processes and the immune response. For now, Aedes aegypti and A. albopictus vectors continue to expand, suggesting that the vaccine will be the most effective means of controlling these viruses. Here we summarize information about these arbovirosis in Argentina and Brazil and describe advances in the development and evaluation of vaccines.

  5. Development and technology transfer of Haemophilus influenzae type b conjugate vaccines for developing countries.

    PubMed

    Beurret, Michel; Hamidi, Ahd; Kreeftenberg, Hans

    2012-07-13

    This paper describes the development of a Haemophilus influenzae type b (Hib) conjugate vaccine at the National Institute for Public Health and the Environment/Netherlands Vaccine Institute (RIVM/NVI, Bilthoven, The Netherlands), and the subsequent transfer of its production process to manufacturers in developing countries. In 1998, at the outset of the project, the majority of the world's children were not immunized against Hib because of the high price and limited supply of the conjugate vaccines, due partly to the fact that local manufacturers in developing countries did not master the Hib conjugate production technology. To address this problem, the RIVM/NVI has developed a robust Hib conjugate vaccine production process based on a proven model, and transferred this technology to several partners in India, Indonesia, Korea and China. As a result, emerging manufacturers in developing countries acquired modern technologies previously unavailable to them. This has in turn facilitated their approach to producing other conjugate vaccines. As an additional spin-off from the project, a World Health Organization (WHO) Hib quality control (QC) course was designed and conducted at the RIVM/NVI, resulting in an increased regulatory capacity for conjugate vaccines in developing countries at the National Regulatory Authority (NRA) level. For the local populations, this has translated into an increased and sustainable supply of affordable Hib conjugate-containing combination vaccines. During the course of this project, developing countries have demonstrated their ability to produce large quantities of high-quality modern vaccines after a successful transfer of the technology. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Addressing diabetes mellitus as part of the strategy for ending TB

    PubMed Central

    Harries, Anthony D.; Kumar, Ajay M.V.; Satyanarayana, Srinath; Lin, Yan; Zachariah, Rony; Lönnroth, Knut; Kapur, Anil

    2016-01-01

    As we enter the new era of Sustainable Development Goals, the international community has committed to ending the TB epidemic by 2030 through implementation of an ambitious strategy to reduce TB-incidence and TB-related mortality and avoiding catastrophic costs for TB-affected families. Diabetes mellitus (DM) triples the risk of TB and increases the probability of adverse TB treatment outcomes such as failure, death and recurrent TB. The rapidly escalating global epidemic of DM means that DM needs to be addressed if TB-related milestones and targets are to be achieved. WHO and the International Union Against Tuberculosis and Lung Disease's Collaborative Framework for Care and Control of Tuberculosis and Diabetes, launched in 2011, provides a template to guide policy makers and implementers to combat the epidemics of both diseases. However, more evidence is required to answer important questions about bi-directional screening, optimal ways of delivering treatment, integration of DM and TB services, and infection control. This should in turn contribute to better and earlier TB case detection, and improved TB treatment outcomes and prevention. DM and TB collaborative care can also help guide the development of a more effective and integrated public health approach for managing non-communicable diseases. PMID:26884497

  7. Private investment in AIDS vaccine development: obstacles and solutions.

    PubMed

    Batson, A; Ainsworth, M

    2001-01-01

    The development of vaccines for the prevention of AIDS, malaria, tuberculosis, and other diseases requires both public and private investment. Private investment, however, has been far lower than might have been hoped, given the massive human toll of these diseases, particularly in the poorest countries. With a view to understanding this situation and exploring potential solutions, the World Bank AIDS Vaccine Task Force commissioned a study on the perspectives of the biotechnology, vaccine, and pharmaceutical industries regarding investment in research and development work on an AIDS vaccine. It was found that different obstacles to the development of an AIDS vaccine arose during the product development cycle. During the earlier phases, before obtaining proof of product, the principal barriers were scientific. The lack of consensus on which approach was likely to be effective increased uncertainty and the risks associated with investing in expensive clinical trials. The later phases, which involved adapting, testing, and scaling up production for different populations, were most influenced by market considerations. In order to raise the levels of private research and development in an AIDS vaccine there will probably have to be a combination of push strategies, which reduce the cost and scientific risk of investment, and pull strategies, which guarantee a market.

  8. Private investment in AIDS vaccine development: obstacles and solutions.

    PubMed Central

    Batson, A.; Ainsworth, M.

    2001-01-01

    The development of vaccines for the prevention of AIDS, malaria, tuberculosis, and other diseases requires both public and private investment. Private investment, however, has been far lower than might have been hoped, given the massive human toll of these diseases, particularly in the poorest countries. With a view to understanding this situation and exploring potential solutions, the World Bank AIDS Vaccine Task Force commissioned a study on the perspectives of the biotechnology, vaccine, and pharmaceutical industries regarding investment in research and development work on an AIDS vaccine. It was found that different obstacles to the development of an AIDS vaccine arose during the product development cycle. During the earlier phases, before obtaining proof of product, the principal barriers were scientific. The lack of consensus on which approach was likely to be effective increased uncertainty and the risks associated with investing in expensive clinical trials. The later phases, which involved adapting, testing, and scaling up production for different populations, were most influenced by market considerations. In order to raise the levels of private research and development in an AIDS vaccine there will probably have to be a combination of push strategies, which reduce the cost and scientific risk of investment, and pull strategies, which guarantee a market. PMID:11545328

  9. Epidemiological Studies to Support the Development of Next Generation Influenza Vaccines.

    PubMed

    Petrie, Joshua G; Gordon, Aubree

    2018-03-26

    The National Institute of Allergy and Infectious Diseases recently published a strategic plan for the development of a universal influenza vaccine. This plan focuses on improving understanding of influenza infection, the development of influenza immunity, and rational design of new vaccines. Epidemiological studies such as prospective, longitudinal cohort studies are essential to the completion of these objectives. In this review, we discuss the contributions of epidemiological studies to our current knowledge of vaccines and correlates of immunity, and how they can contribute to the development and evaluation of the next generation of influenza vaccines. These studies have been critical in monitoring the effectiveness of current influenza vaccines, identifying issues such as low vaccine effectiveness, reduced effectiveness among those who receive repeated vaccination, and issues related to egg adaptation during the manufacturing process. Epidemiological studies have also identified population-level correlates of protection that can inform the design and development of next generation influenza vaccines. Going forward, there is an enduring need for epidemiological studies to continue advancing knowledge of correlates of protection and the development of immunity, to evaluate and monitor the effectiveness of next generation influenza vaccines, and to inform recommendations for their use.

  10. Role of nanotechnology in HIV/AIDS vaccine development.

    PubMed

    Liu, Ying; Chen, Chunying

    2016-08-01

    HIV/AIDS is one of the worst crises affecting global health and influencing economic development and social stability. Preventing and treating HIV infection is a crucial task. However, there is still no effective HIV vaccine for clinical application. Nanotechnology has the potential to solve the problems associated with traditional HIV vaccines. At present, various nano-architectures and nanomaterials can function as potential HIV vaccine carriers or adjuvants, including inorganic nanomaterials, liposomes, micelles and polymer nanomaterials. In this review, we summarize the current progress in the use of nanotechnology for the development of an HIV/AIDS vaccine and discuss its potential to greatly improve the solubility, permeability, stability and pharmacokinetics of HIV vaccines. Although nanotechnology holds great promise for applications in HIV/AIDS vaccines, there are still many inadequacies that result in a variety of risks and challenges. The potential hazards to the human body and environment associated with some nano-carriers, and their underlying mechanisms require in-depth study. Non-toxic or low-toxic nanomaterials with adjuvant activity have been identified. However, studying the confluence of factors that affect the adjuvant activity of nanomaterials may be more important for the optimization of the dosage and immunization strategy and investigations into the exact mechanism of action. Moreover, there are no uniform standards for investigations of nanomaterials as potential vaccine adjuvants. These limitations make it harder to analyze and deduce rules from the existing data. Developing vaccine nano-carriers or adjuvants with high benefit-cost ratios is important to ensure their broad usage. Despite some shortcomings, nanomaterials have great potential and application prospects in the fields of AIDS treatment and prevention. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Current Status of Rift Valley Fever Vaccine Development

    PubMed Central

    Faburay, Bonto; LaBeaud, Angelle Desiree; McVey, D. Scott; Wilson, William C.; Richt, Juergen A.

    2017-01-01

    Rift Valley Fever (RVF) is a mosquito-borne zoonotic disease that presents a substantial threat to human and public health. It is caused by Rift Valley fever phlebovirus (RVFV), which belongs to the genus Phlebovirus and the family Phenuiviridae within the order Bunyavirales. The wide distribution of competent vectors in non-endemic areas coupled with global climate change poses a significant threat of the transboundary spread of RVFV. In the last decade, an improved understanding of the molecular biology of RVFV has facilitated significant progress in the development of novel vaccines, including DIVA (differentiating infected from vaccinated animals) vaccines. Despite these advances, there is no fully licensed vaccine for veterinary or human use available in non-endemic countries, whereas in endemic countries, there is no clear policy or practice of routine/strategic livestock vaccinations as a preventive or mitigating strategy against potential RVF disease outbreaks. The purpose of this review was to provide an update on the status of RVF vaccine development and provide perspectives on the best strategies for disease control. Herein, we argue that the routine or strategic vaccination of livestock could be the best control approach for preventing the outbreak and spread of future disease. PMID:28925970

  12. Mucosal Vaccine Development Based on Liposome Technology

    PubMed Central

    Norling, Karin; Bally, Marta; Höök, Fredrik

    2016-01-01

    Immune protection against infectious diseases is most effective if located at the portal of entry of the pathogen. Hence, there is an increasing demand for vaccine formulations that can induce strong protective immunity following oral, respiratory, or genital tract administration. At present, only few mucosal vaccines are found on the market, but recent technological advancements and a better understanding of the principles that govern priming of mucosal immune responses have contributed to a more optimistic view on the future of mucosal vaccines. Compared to live attenuated vaccines, subcomponent vaccines, most often protein-based, are considered safer, more stable, and less complicated to manufacture, but they require the addition of nontoxic and clinically safe adjuvants to be effective. In addition, another limiting factor is the large antigen dose that usually is required for mucosal vaccines. Therefore, the combination of mucosal adjuvants with the recent progress in nanoparticle technology provides an attractive solution to these problems. In particular, the liposome technology is ideal for combining protein antigen and adjuvant into an effective mucosal vaccine. Here, we describe and discuss recent progress in nanoparticle formulations using various types of liposomes that convey strong promise for the successful development of the next generation of mucosal vaccines. PMID:28127567

  13. Vaccines in development against West Nile virus.

    PubMed

    Brandler, Samantha; Tangy, Frederic

    2013-09-30

    West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV) disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV) vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine.

  14. "Communicate to vaccinate": the development of a taxonomy of communication interventions to improve routine childhood vaccination.

    PubMed

    Willis, Natalie; Hill, Sophie; Kaufman, Jessica; Lewin, Simon; Kis-Rigo, John; De Castro Freire, Sara Bensaude; Bosch-Capblanch, Xavier; Glenton, Claire; Lin, Vivian; Robinson, Priscilla; Wiysonge, Charles S

    2013-05-11

    Vaccination is a cost-effective public health measure and is central to the Millennium Development Goal of reducing child mortality. However, childhood vaccination coverage remains sub-optimal in many settings. While communication is a key feature of vaccination programmes, we are not aware of any comprehensive approach to organising the broad range of communication interventions that can be delivered to parents and communities to improve vaccination coverage. Developing a classification system (taxonomy) organised into conceptually similar categories will aid in: understanding the relationships between different types of communication interventions; facilitating conceptual mapping of these interventions; clarifying the key purposes and features of interventions to aid implementation and evaluation; and identifying areas where evidence is strong and where there are gaps. This paper reports on the development of the 'Communicate to vaccinate' taxonomy. The taxonomy was developed in two stages. Stage 1 included: 1) forming an advisory group; 2) searching for descriptions of interventions in trials (CENTRAL database) and general health literature (Medline); 3) developing a sampling strategy; 4) screening the search results; 5) developing a data extraction form; and 6) extracting intervention data. Stage 2 included: 1) grouping the interventions according to purpose; 2) holding deliberative forums in English and French with key vaccination stakeholders to gather feedback; 3) conducting a targeted search of grey literature to supplement the taxonomy; 4) finalising the taxonomy based on the input provided. The taxonomy includes seven main categories of communication interventions: inform or educate, remind or recall, teach skills, provide support, facilitate decision making, enable communication and enhance community ownership. These categories are broken down into 43 intervention types across three target groups: parents or soon-to-be-parents; communities, community

  15. Engineering Mycobacteria for the Production of Self-Assembling Biopolyesters Displaying Mycobacterial Antigens for Use as a Tuberculosis Vaccine.

    PubMed

    Lee, Jason W; Parlane, Natalie A; Rehm, Bernd H A; Buddle, Bryce M; Heiser, Axel

    2017-03-01

    Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis or Mycobacterium bovis and still remains one of the world's biggest global health burdens. Recently, engineered polyhydroxyalkanoate (PHA) biobeads that were produced in both Escherichia coli and Lactococcus lactis and displayed mycobacterial antigens were found to induce significant cell-mediated immune responses in mice. We observed that such PHA beads contained host cell proteins as impurities, which we hypothesized to have the potential to induce immunity. In this study, we aimed to develop PHA beads produced in mycobacteria (mycobacterial PHA biobeads [MBB]) and test their potential as a TB vaccine in a mouse model. As a model organism, nonpathogenic Mycobacterium smegmatis was engineered to produce MBB or MBB with immobilized mycobacterial antigens Ag85A and ESAT-6 on their surface (A:E-MBB). Three key enzymes involved in the poly(3-hydroxybutyric acid) pathway, namely, β-ketothiolase (PhaA), acetoacetyl-coenzyme A reductase (PhaB), and PHA synthase (PhaC), were engineered into E. coli - Mycobacterium shuttle plasmids and expressed in trans Immobilization of specific antigens to the surface of the MBB was achieved by creating a fusion with the PHA synthase which remains covalently attached to the polyester core, resulting in PHA biobeads displaying covalently immobilized antigens. E-MBB, and an M. smegmatis vector control (MVC) were used in a mouse immunology trial, with comparison to phosphate-buffered saline (PBS)-vaccinated and Mycobacterium bovis BCG-vaccinated groups. We successfully produced MBB and A:E-MBB and used them as vaccines to induce a cellular immune response to mycobacterial antigens. IMPORTANCE Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis or Mycobacterium bovis and still remains one of the world's biggest global health burdens. In this study, we produced polyhydroxyalkanoate (PHA) biobeads in mycobacteria and used them as vaccines to induce a cellular

  16. Engineering Mycobacteria for the Production of Self-Assembling Biopolyesters Displaying Mycobacterial Antigens for Use as a Tuberculosis Vaccine

    PubMed Central

    Lee, Jason W.; Parlane, Natalie A.; Rehm, Bernd H. A.; Buddle, Bryce M.

    2017-01-01

    ABSTRACT Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis or Mycobacterium bovis and still remains one of the world's biggest global health burdens. Recently, engineered polyhydroxyalkanoate (PHA) biobeads that were produced in both Escherichia coli and Lactococcus lactis and displayed mycobacterial antigens were found to induce significant cell-mediated immune responses in mice. We observed that such PHA beads contained host cell proteins as impurities, which we hypothesized to have the potential to induce immunity. In this study, we aimed to develop PHA beads produced in mycobacteria (mycobacterial PHA biobeads [MBB]) and test their potential as a TB vaccine in a mouse model. As a model organism, nonpathogenic Mycobacterium smegmatis was engineered to produce MBB or MBB with immobilized mycobacterial antigens Ag85A and ESAT-6 on their surface (A:E-MBB). Three key enzymes involved in the poly(3-hydroxybutyric acid) pathway, namely, β-ketothiolase (PhaA), acetoacetyl-coenzyme A reductase (PhaB), and PHA synthase (PhaC), were engineered into E. coli-Mycobacterium shuttle plasmids and expressed in trans. Immobilization of specific antigens to the surface of the MBB was achieved by creating a fusion with the PHA synthase which remains covalently attached to the polyester core, resulting in PHA biobeads displaying covalently immobilized antigens. MBB, A:E-MBB, and an M. smegmatis vector control (MVC) were used in a mouse immunology trial, with comparison to phosphate-buffered saline (PBS)-vaccinated and Mycobacterium bovis BCG-vaccinated groups. We successfully produced MBB and A:E-MBB and used them as vaccines to induce a cellular immune response to mycobacterial antigens. IMPORTANCE Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis or Mycobacterium bovis and still remains one of the world's biggest global health burdens. In this study, we produced polyhydroxyalkanoate (PHA) biobeads in mycobacteria and used them as vaccines to

  17. HIV vaccine: Can it be developed in the 21st century?

    PubMed

    Verma, Ramesh; Khanna, Pardeep; Chawla, Suraj; Dhankar, Mukesh

    2016-01-01

    HIV infection is a major public health problem especially in the developing countries. Once a person infects with HIV, it remained infected for lifelong. The advanced stage developed after 10-15 y of HIV infection that stage is called acquired immunodeficiency syndrome (AIDS). From 1990 to 2000 the number of people living with HIV rose from 8 million to 27 million; since the beginning of the HIV/AIDS epidemic, AIDS has claimed almost 39million lives so far. Till now, there is no cure for HIV infection; however, after the introduction of effective treatment with antiretroviral (ARV) drugs the HIV individual can enjoy healthy and productive lives. Vaccine is safe and cost-effective to prevent illness, impairment, disability and death. Like other vaccines, a preventive HIV vaccine could help save millions of lives. All vaccines work the same way i.e. the antigen stimulate the immune system and develop antibodies. The ultimate goal is to develop a safe and effective vaccine that protects people worldwide from getting infected with HIV. However, some school of thought that vaccine may protects only some HIV people, it could have a major impact on the rates of transmission of HIV and this will help in control of epidemic, especially in populations where high rate of HIV transmission. In the past, some scientist doubted on the development of an effective polio vaccine, but now we are near to eradicate the polio from the world this is possible because of successful vaccination programmes. HIV vaccine research is aided by the not-for-profit International AIDS/HIV vaccine Initiative (IAVI), which helps to support and coordinate vaccine research, development, policy and advocacy around the world. Although the challenges for scientist are intimidating but scientists remain hopeful that they can develop safe and effective HIV vaccines for patients in future.

  18. Prolonged intervals during Mycobacterium tuberculosis subunit vaccine boosting contributes to eliciting immunity mediated by central memory-like T cells.

    PubMed

    Bai, Chunxiang; He, Juanjuan; Niu, Hongxia; Hu, Lina; Luo, Yanping; Liu, Xun; Peng, Liang; Zhu, Bingdong

    2018-05-01

    It is believed that central memory T cells (T CM ) provide long-term protection against tuberculosis (TB). However, the effects of TB subunit vaccine immunization schedule, especially the vaccination intervals, on T cell immune memory is still unclear. In this study, mice were immunized with fusion protein ESAT6-Ag85B-MPT64 (190-198)-Mtb8.4-Rv2626c (LT70) based subunit vaccine three times according to the following schedules: ① 0, 3rd and 6th week respectively (0-3-6w), ② 0, 4th and 12th week (0-4-12w), and ③ 0, 4th and 24th week (0-4-24w). We found that both schedules of 0-4-12w and 0-4-24w induced higher level of antigen specific IL-2, IFN-γ and TNF-α than 0-3-6w immunization. Among them, 0-4-12w induced the highest level of IL-2, which is a key cytokine mainly produced by T CM . Moreover, by cultured IFN-γ ELISPOT and cell proliferation assay etc., we found that the vaccination schedule of 0-4-12w elicited higher numbers of T CM like cells, stronger T CM - mediated immune responses and higher protective efficacy against M. bovis BCG challenge than 0-3-6w did. It suggests that prolonging the vaccination interval of TB subunit vaccine to some extent contributes to inducing more abundant T CM like cells and providing stronger immune protection against mycobacteria infection. Copyright © 2018. Published by Elsevier Ltd.

  19. Intellectual property rights and challenges for development of affordable human papillomavirus, rotavirus and pneumococcal vaccines: Patent landscaping and perspectives of developing country vaccine manufacturers.

    PubMed

    Chandrasekharan, Subhashini; Amin, Tahir; Kim, Joyce; Furrer, Eliane; Matterson, Anna-Carin; Schwalbe, Nina; Nguyen, Aurélia

    2015-11-17

    The success of Gavi, the Vaccine Alliance depends on the vaccine markets providing appropriate, affordable vaccines at sufficient and reliable quantities. Gavi's current supplier base for new and underutilized vaccines, such as the human papillomavirus (HPV), rotavirus, and the pneumococcal conjugate vaccine is very small. There is growing concern that following globalization of laws on intellectual property rights (IPRs) through trade agreements, IPRs are impeding new manufacturers from entering the market with competing vaccines. This article examines the extent to which IPRs, specifically patents, can create such obstacles, in particular for developing country vaccine manufacturers (DCVMs). Through building patent landscapes in Brazil, China, and India and interviews with manufacturers and experts in the field, we found intense patenting activity for the HPV and pneumococcal vaccines that could potentially delay the entry of new manufacturers. Increased transparency around patenting of vaccine technologies, stricter patentability criteria suited for local development needs and strengthening of IPRs management capabilities where relevant, may help reduce impediments to market entry for new manufacturers and ensure a competitive supplier base for quality vaccines at sustainably low prices. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. High-Density Peptide Arrays for Malaria Vaccine Development.

    PubMed

    Loeffler, Felix F; Pfeil, Johannes; Heiss, Kirsten

    2016-01-01

    The development of an efficacious and practicable vaccine conferring sterile immunity towards a Plasmodium infection represents a not yet achieved goal. A crucial factor for the impact of a given anti-plasmodial subunit vaccine is the identification of the most potent parasitic components required to induce protection from both infection and disease. Here, we present a method based on a novel high-density peptide array technology that allows for a flexible readout of malaria antibodies. Peptide arrays applied as a screening method can be used to identify novel immunogenic antibody epitopes under a large number of potential antigens/peptides. Ultimately, discovered antigen candidates and/or epitope sequences can be translated into vaccine prototype design. The technology can be further utilized to unravel antibody-mediated immune responses (e.g., involved in the establishment of semi-immunity) and moreover to confirm vaccine potency during the process of clinical development by verifying the induced antibody responses following vaccination.

  1. Microneedle-based vaccines

    PubMed Central

    Prausnitz, Mark R.; Mikszta, John A.; Cormier, Michel; Andrianov, Alexander K.

    2010-01-01

    The threat of pandemic influenza and other public health needs motivates development of better vaccine delivery systems. To address this need, microneedles have been developed as micron-scale needles fabricated using low-cost manufacturing methods that administer vaccine into the skin using a simple device that may be suitable for self-administration. Delivery using solid or hollow microneedles can be accomplished by (i) piercing the skin and then applying a vaccine formulation or patch onto the permeabilized skin, (ii) coating or encapsulating vaccine onto or within microneedles for rapid, or delayed, dissolution and release in the skin and (iii) injection into the skin using a modified syringe or pump. Extensive clinical experience with smallpox, TB and other vaccines has shown that vaccine delivery into the skin using conventional intradermal injection is generally safe and effective and often elicits the same immune responses at lower doses compared to intramuscular injection. Animal experiments using microneedles have shown similar benefits. Microneedles have been used to deliver whole, inactivated virus; trivalent split antigen vaccines; and DNA plasmid encoding the influenza hemagglutinin to rodents and found strong antibody responses. In addition, ChimeriVax™-JE against yellow fever was administered to non-human primates and generated protective levels of neutralizing antibodies more than seven times greater than subcutaneous delivery; DNA plasmid encoding hepatitis B surface antigen was administered to mice and generated antibody and T cell responses at least as strong as hypodermic injections; recombinant Protective Antigen of Baccilus anthracis was administered to rabbits and provided complete protection from lethal aerosol anthrax spore challenge at a lower dose than intramuscular injection; and DNA plasmid encoding four vaccinia virus genes administered to mice in combination with electroporation generated neutralizing antibodies that apparently

  2. Advances in the development of next-generation anthrax vaccines.

    PubMed

    Friedlander, Arthur M; Little, Stephen F

    2009-11-05

    Anthrax, a disease of herbivores, only rarely infects humans. However, the threat of using Bacillus anthracis, the causative agent, to intentionally produce disease has been the impetus for development of next-generation vaccines. Two licensed vaccines have been available for human use for several decades. These are composed of acellular culture supernatants containing the protective antigen (PA) component of the anthrax toxins. In this review we summarize the various approaches used to develop improved vaccines. These efforts have included the use of PA with newer adjuvants and delivery systems, including bacterial and viral vectors and DNA vaccines. Attempts to broaden the protection afforded by PA-based vaccines have focused on adding other B. anthracis components, including spore and capsule antigens.

  3. Malaria transmission blocking immunity and sexual stage vaccines for interrupting malaria transmission in Latin America

    PubMed Central

    Arévalo-Herrera, Myriam; Solarte, Yezid; Marin, Catherin; Santos, Mariana; Castellanos, Jenniffer; Beier, John C; Valencia, Sócrates Herrera

    2016-01-01

    Malaria is a vector-borne disease that is considered to be one of the most serious public health problems due to its high global mortality and morbidity rates. Although multiple strategies for controlling malaria have been used, many have had limited impact due to the appearance and rapid dissemination of mosquito resistance to insecticides, parasite resistance to multiple antimalarial drug, and the lack of sustainability. Individuals in endemic areas that have been permanently exposed to the parasite develop specific immune responses capable of diminishing parasite burden and the clinical manifestations of the disease, including blocking of parasite transmission to the mosquito vector. This is referred to as transmission blocking (TB) immunity (TBI) and is mediated by specific antibodies and other factors ingested during the blood meal that inhibit parasite development in the mosquito. These antibodies recognize proteins expressed on either gametocytes or parasite stages that develop in the mosquito midgut and are considered to be potential malaria vaccine candidates. Although these candidates, collectively called TB vaccines (TBV), would not directly stop malaria from infecting individuals, but would stop transmission from infected person to non-infected person. Here, we review the progress that has been achieved in TBI studies and the development of TBV and we highlight their potential usefulness in areas of low endemicity such as Latin America. PMID:21881775

  4. Public-private mix for TB and TB-HIV care in Lagos, Nigeria.

    PubMed

    Daniel, O J; Adedeji Adejumo, O; Abdur-Razzaq, H A; Ngozi Adejumo, E; Salako, A A

    2013-09-01

    Private and public tuberculosis (TB) treatment centres in Lagos State, Nigeria. To assess the contribution of private health care providers to TB and TB-HIV (human immunodeficiency virus) case finding in Lagos State. A retrospective review of programme data submitted to the Lagos State TB and Leprosy Control Programme in 2011 by public, private for-profit (PFP) and private not-for-profit (PNFP) health care providers. A total of 8425 TB cases were notified by 31 private (11 PFP and 20 PNFP) and 99 public health facilities in Lagos State. Overall, the private facilities were responsible for 10.3% (866/8425) of the total TB cases notified. The proportion of TB patients tested for HIV was respectively 86.2%, 53.1% and 96.5% among public, PFP and PNFP facilities. Overall, 22.4% of the TB patients were HIV-positive. The HIV positivity rate among public, PFP and PNFP facilities was respectively 23.8%, 7.8% and 9.9%. Uptake of cotrimoxazole preventive therapy was respectively 69.6%, 25% and 38.2% among public, PFP and PNFP facilities, while that of antiretroviral therapy was respectively 23.8%, 8.3% and 9.1% in public, PFP and PNFP facilities. There is a need to scale up collaboration with the private sector, and particularly PNFP health providers.

  5. Status of vaccine research and development of vaccines for GBS.

    PubMed

    Heath, Paul T

    2016-06-03

    Streptococcus agalactiae (group B streptococcus (GBS)) is the leading cause of neonatal sepsis and meningitis in many countries. Intrapartum antibiotic strategies have reduced the incidence of early-onset neonatal GBS in a number of countries but have had no impact on late onset GBS infection (LOD). In low/middle income settings, the disease burden remains uncertain although in several countries of Southern Africa appears comparable to or higher than that of high-income countries. As disease may be rapidly fulminating cases can be missed before appropriate samples are obtained and this may lead to underestimation of the true burden. Given the rapid onset and progression within hours of birth as well as the deficiencies in IAP strategies and absence of a solution for preventing LOD, it is clear that administration of a suitable vaccine in pregnancy could provide a better solution in all settings; it should also be cost effective. The current leading vaccine candidates are CPS-protein conjugate vaccines but protein-based vaccines are also in development and one has recently commenced clinical trials. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  6. Roads to the development of improved pertussis vaccines paved by immunology

    PubMed Central

    Brummelman, Jolanda; Wilk, Mieszko M.; Han, Wanda G.H.; van Els, Cécile A.C.M.; Mills, Kingston H.G.

    2015-01-01

    Current acellular pertussis vaccines have various shortcomings, which may contribute to their suboptimal efficacy and waning immunity in vaccinated populations. This calls for the development of new pertussis vaccines capable of inducing long-lived protective immunity. Immunization with whole cell pertussis vaccines and natural infection with Bordetella pertussis induce distinct and more protective immune responses when compared with immunization with acellular pertussis vaccines. Therefore, the immune responses induced with whole cell vaccine or after infection can be used as a benchmark for the development of third-generation vaccines against pertussis. Here, we review the literature on the immunology of B. pertussis infection and vaccination and discuss the lessons learned that will help in the design of improved pertussis vaccines. PMID:26347400

  7. Status of vaccine research and development of vaccines for Nipah virus.

    PubMed

    Satterfield, Benjamin A; Dawes, Brian E; Milligan, Gregg N

    2016-06-03

    Nipah virus (NiV) is a highly pathogenic, recently emerged paramyxovirus that has been responsible for sporadic outbreaks of respiratory and encephalitic disease in Southeast Asia. High case fatality rates have also been associated with recent outbreaks in Malaysia and Bangladesh. Although over two billion people currently live in regions in which NiV is endemic or in which the Pteropus fruit bat reservoir is commonly found, there is no approved vaccine to protect against NiV disease. This report examines the feasibility and current efforts to develop a NiV vaccine including potential hurdles for technical and regulatory assessment of candidate vaccines and the likelihood for financing. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  8. Tuberculosis Facts - TB Can Be Treated

    MedlinePlus

    Tuberculosis (TB) Facts TB Can Be Treated What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination Page 1 of 2 TB Facts: TB ...

  9. Tuberculosis Facts - You Can Prevent TB

    MedlinePlus

    Tuberculosis (TB) Facts You Can Prevent TB What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination TB Facts: You Can Prevent TB What ...

  10. Development of respiratory syncytial virus (RSV) vaccines for infants.

    PubMed

    Gerretsen, Hannah E; Sande, Charles J

    2017-06-01

    2017 will mark the 60 th anniversary since the first isolation of RSV in children. In spite of concerted efforts over all these years, the goal of developing an effective vaccine against paediatric RSV disease has remained elusive. One of the main hurdles standing in the way of an effective vaccine is the fact that the age incidence of severe disease peaks within the first 3 months of life, providing limited opportunity for intervention. In addition to this complexity, the spectre of failed historical vaccines, which increased the risk of illness and death upon subsequent natural infection, has substantially increased the safety criteria against which modern vaccines will be assessed. This review traces the history of RSV vaccine development for young infants and analyses the potential reasons for the failure of historic vaccines. It also discusses recent breakthroughs in vaccine antigen design and the progressive evolution of platforms for the delivery of these antigens to seronegative infants. © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  11. Lessons learned during the development and transfer of technology related to a new Hib conjugate vaccine to emerging vaccine manufacturers.

    PubMed

    Hamidi, A; Boog, C; Jadhav, S; Kreeftenberg, H

    2014-07-16

    The incidence of Haemophilus Influenzae type b (Hib) disease in developed countries has decreased since the introduction of Hib conjugate vaccines in their National Immunization Programs (NIP). In countries where Hib vaccination is not applied routinely, due to limited availability and high cost of the vaccines, invasive Hib disease is still a cause of mortality. Through the development of a production process for a Hib conjugate vaccine and related quality control tests and the transfer of this technology to emerging vaccine manufacturers in developing countries, a substantial contribution was made to the availability and affordability of Hib conjugate vaccines in these countries. Technology transfer is considered to be one of the fastest ways to get access to the technology needed for the production of vaccines. The first Hib conjugate vaccine based on the transferred technology was licensed in 2007, since then more Hib vaccines based on this technology were licensed. This paper describes the successful development and transfer of Hib conjugate vaccine technology to vaccine manufacturers in India, China and Indonesia. By describing the lessons learned in this process, it is hoped that other technology transfer projects can benefit from the knowledge and experience gained. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Development of Sanofi Pasteur tetravalent dengue vaccine.

    PubMed

    Guy, Bruno; Saville, Melanie; Lang, Jean

    2010-09-16

    The Sanofi Pasteur tetravalent dengue vaccine candidate is composed of 4 recombinant live attenuated vaccines based on a yellow fever vaccine 17D (YFV 17D) backbone, each expressing the prM and envelope genes of one of the four dengue virus serotypes. Pre-clinical studies have demonstrated that the TV dengue vaccine is genetically and phenotypically stable, non-hepatotropic, less neurovirulent than YFV 17D and does not infect mosquitoes by the oral route. In vitro and in vivo preclinical studies also showed that the TV dengue vaccine induced controlled stimulation in human dendritic cells and significant immune responses in monkeys. TV dengue vaccine reactogenicity, viraemia induction and antibody responses were investigated in three Phase I trials in the USA, the Philippines and Mexico, in a two or three-dose regimen over a 12 month period. Results showed that the majority of adverse events were mild to moderate and transient in nature. Viraemia was transient and low, and was not increased after initial dengue TV administration, even in the case of incomplete responses. ϕSeropositivity [≥10 in a PRNT 50 assay] was 100% for all four serotypes in flavivirus-naive adults injected with 3 doses of TV dengue vaccine in the USA. Similarly, seropositivity was 88-100% following three administrations in flavivirus-naive Mexican children aged 2-5 years. Furthermore, the proportion of seropositive subjects increased with each dengue TV injection in the Philippines where baseline flavivirus immunity was high. Responses were also monitored at the cellular level in humans, and their level and nature were in good agreement with the observed safety and the immunogenicity of the vaccine. Finally, the challenges inherent to the development of such TV dengue vaccines will also be discussed in the last part of this review. In conclusion, preclinical and clinical results support the favorable immunogenicity and short-term safety of the dengue TV vaccine. An extensive clinical

  13. Vaccine development for emerging virulent infectious diseases.

    PubMed

    Maslow, Joel N

    2017-10-04

    The recent outbreak of Zaire Ebola virus in West Africa altered the classical paradigm of vaccine development and that for emerging infectious diseases (EIDs) in general. In this paper, the precepts of vaccine discovery and advancement through pre-clinical and clinical assessment are discussed in the context of the recent Ebola virus, Middle East Respiratory Syndrome coronavirus (MERS-CoV), and Zika virus outbreaks. Clinical trial design for diseases with high mortality rates and/or high morbidity in the face of a global perception of immediate need and the factors that drive design in the face of a changing epidemiology are presented. Vaccines for EIDs thus present a unique paradigm to standard development precepts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. A potential disruptive technology in vaccine development: gene-based vaccines and their application to infectious diseases.

    PubMed

    Kaslow, David C

    2004-10-01

    Vaccine development requires an amalgamation of disparate disciplines and has unique economic and regulatory drivers. Non-viral gene-based delivery systems, such as formulated plasmid DNA, are new and potentially disruptive technologies capable of providing 'cheaper, simpler, and more convenient-to-use' vaccines. Typically and somewhat ironically, disruptive technologies have poorer product performance, at least in the near-term, compared with the existing conventional technologies. Because successful product development requires that the product's performance must meet or exceed the efficacy threshold for a desired application, the appropriate selection of the initial product applications for a disruptive technology is critical for its successful evolution. In this regard, the near-term successes of gene-based vaccines will likely be for protection against bacterial toxins and acute viral and bacterial infections. Recent breakthroughs, however, herald increasing rather than languishing performance improvements in the efficacy of gene-based vaccines. Whether gene-based vaccines ultimately succeed in eliciting protective immunity in humans to persistent intracellular pathogens, such as HIV, malaria and tuberculosis, for which the conventional vaccine technologies have failed, remains to be determined. A success against any one of the persistent intracellular pathogens would be sufficient proof that gene-based vaccines represent a disruptive technology against which future vaccine technologies will be measured.

  15. The path of malaria vaccine development: challenges and perspectives.

    PubMed

    Arama, C; Troye-Blomberg, M

    2014-05-01

    Malaria is a life-threatening disease caused by parasites of the Plasmodium genus. In many parts of the world, the parasites have developed resistance to a number of antimalarial agents. Key interventions to control malaria include prompt and effective treatment with artemisinin-based combination therapies, use of insecticidal nets by individuals at risk and active research into malaria vaccines. Protection against malaria through vaccination was demonstrated more than 30 years ago when individuals were vaccinated via repeated bites by Plasmodium falciparum-infected and irradiated but still metabolically active mosquitoes. However, vaccination with high doses of irradiated sporozoites injected into humans has long been considered impractical. Yet, following recent success using whole-organism vaccines, the approach has received renewed interest; it was recently reported that repeated injections of irradiated sporozoites increased protection in 80 vaccinated individuals. Other approaches include subunit malaria vaccines, such as the current leading candidate RTS,S (consisting of fusion between a portion of the P. falciparum-derived circumsporozoite protein and the hepatitis B surface antigen), which has been demonstrated to induce reasonably good protection. Although results have been encouraging, the level of protection is generally considered to be too low to achieve eradication of malaria. There is great interest in developing new and better formulations and stable delivery systems to improve immunogenicity. In this review, we will discuss recent strategies to develop efficient malaria vaccines. © 2014 The Association for the Publication of the Journal of Internal Medicine.

  16. Vaccines in Development against West Nile Virus

    PubMed Central

    Brandler, Samantha; Tangy, Frederic

    2013-01-01

    West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV) disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV) vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine. PMID:24084235

  17. Military Infectious Diseases Update on Vaccine Development

    DTIC Science & Technology

    2011-01-24

    Research Program (MIDRP) Insect Vector ControlDiagnostics Prevention Treatment Infectious diseases adversely impact military operations. Vaccines...appropriate treatment and aids commanders in the field. Most militarily relevant infectious diseases are transmitted by biting insects and other...based Insect Repellent (1946) Vaccines Protectants Antiparasitic Drugs Research Effort Advanced Development Fielded Products Malaria Rapid

  18. Killed oral cholera vaccines: history, development and implementation challenges.

    PubMed

    Lopez, Anna Lena; Gonzales, Maria Liza Antoinette; Aldaba, Josephine G; Nair, G Balakrish

    2014-09-01

    Cholera is still a major global health problem, affecting mainly people living in unsanitary conditions and who are at risk for outbreaks of cholera. During the past decade, outbreaks are increasingly reported from more countries. From the early killed oral cholera vaccine, rapid improvements in vaccine development occurred as a result of a better understanding of the epidemiology of the disease, pathogenesis of cholera infection and immunity. The newer-generation oral killed cholera vaccines have been shown to be safe and effective in field trials conducted in cholera endemic areas. Likewise, they have been shown to be protective when used during outbreak settings. Aside from providing direct protection to vaccinated individuals, recent studies have demonstrated that these killed oral vaccines also confer indirect protection through herd immunity. Although new-generation oral cholera vaccines should not be considered in isolation from other preventive approaches in countries where they are most needed, especially improved water quality and sanitation, these vaccines serve as immediately available public health tools for preventing further morbidity and mortality from cholera. However, despite its availability for more than two decades, use of these vaccines has not been optimized. Although there are limitations of the currently available oral cholera vaccines, recent data show that the vaccines are safe, feasible to use even in difficult circumstances and able to provide protection in various settings. Clear identification of the areas and target population groups who will benefit from the use of the cholera vaccines will be required and strategies to facilitate accessibility and usage of these vaccines in these areas and population groups will need to be developed.

  19. The clinical development process for a novel preventive vaccine: An overview.

    PubMed

    Singh, K; Mehta, S

    2016-01-01

    Each novel vaccine candidate needs to be evaluated for safety, immunogenicity, and protective efficacy in humans before it is licensed for use. After initial safety evaluation in healthy adults, each vaccine candidate follows a unique development path. This article on clinical development gives an overview on the development path based on the expectations of various guidelines issued by the World Health Organization (WHO), the European Medicines Agency (EMA), and the United States Food and Drug Administration (USFDA). The manuscript describes the objectives, study populations, study designs, study site, and outcome(s) of each phase (Phase I-III) of a clinical trial. Examples from the clinical development of a malaria vaccine candidate, a rotavirus vaccine, and two vaccines approved for human papillomavirus (HPV) have also been discussed. The article also tabulates relevant guidelines, which can be referred to while drafting the development path of a novel vaccine candidate.

  20. Framework of behavioral indicators evaluating TB health promotion outcomes: a modified Delphi study of TB policymakers and health workers.

    PubMed

    Li, Ying; Ehiri, John; Hu, Daiyu; Oren, Eyal; Cao, Jia

    2015-12-15

    Although TB health promotion directed at policy makers and healthcare workers (HCWs) is considered important to tuberculosis (TB) control, no indicators currently assess the impact of such promotional activities. This article is the second in a series of papers that seek to establish a framework of behavioral indicators for outcome evaluation of TB health promotion, using the Delphi method. In the first article, we sought to establish a framework of behavioral indicators for outcome evaluation of TB health promotion among TB suspects and patients. The objective of this second article is to present an indicator framework that can be used to assess behavioral outcomes of TB health promotion directed at policy makers and HCWs. A two-round, modified Delphi method was used to establish the indicators. Sixteen experts who were knowledgeable and experienced in the field of TB control were consulted in Delphi surveys. A questionnaire was developed following 4 steps, and involved ranking indicators on a five-point Likert scale. The consensus level was 70 %. Median, mode, and Coefficient of variation (CV) were used to describe expert responses. An authority coefficient (Cr) was used to assess the degree of each expert's authority. Consensus was achieved following the two survey rounds and several iterations among the experts. For TB health-promotion activities directed at policymakers, the experts reached consensus on 2 domains ("Resource inputs" and "Policymaking and monitoring behaviors"), 4 subdomains ("Human resources" among others), and 13 indicators ("Human resources per 100,000 person" among others). For TB health-promotion activities directed at HCWs, the experts reached consensus on 5 domains ("Self-protective behaviors" among others), 6 sub-domains ("Preventing infection" among others), and 15 indicators ("Average hours of daily workplace disinfection by ultraviolet radiation" among others). This study identified a conceptual framework of core behavioral indicators

  1. Experience and challenges from clinical trials with malaria vaccines in Africa

    PubMed Central

    2013-01-01

    Malaria vaccines are considered amongst the most important modalities for potential elimination of malaria disease and transmission. Research and development in this field has been an area of intense effort by many groups over the last few decades. Despite this, there is currently no licensed malaria vaccine. Researchers, clinical trialists and vaccine developers have been working on many approached to make malaria vaccine available. African research institutions have developed and demonstrated a great capacity to undertake clinical trials in accordance to the International Conference on Harmonization-Good Clinical Practice (ICH-GCP) standards in the last decade; particularly in the field of malaria vaccines and anti-malarial drugs. This capacity is a result of networking among African scientists in collaboration with other partners; this has traversed both clinical trials and malaria control programmes as part of the Global Malaria Action Plan (GMAP). GMAP outlined and support global strategies toward the elimination and eradication of malaria in many areas, translating in reduction in public health burden, especially for African children. In the sub-Saharan region the capacity to undertake more clinical trials remains small in comparison to the actual need. However, sustainability of the already developed capacity is essential and crucial for the evaluation of different interventions and diagnostic tools/strategies for other diseases like TB, HIV, neglected tropical diseases and non-communicable diseases. There is urgent need for innovative mechanisms for the sustainability and expansion of the capacity in clinical trials in sub-Saharan Africa as the catalyst for health improvement and maintained. PMID:23496910

  2. Experience and challenges from clinical trials with malaria vaccines in Africa.

    PubMed

    Mwangoka, Grace; Ogutu, Bernhards; Msambichaka, Beverly; Mzee, Tutu; Salim, Nahya; Kafuruki, Shubis; Mpina, Maxmillian; Shekalaghe, Seif; Tanner, Marcel; Abdulla, Salim

    2013-03-04

    Malaria vaccines are considered amongst the most important modalities for potential elimination of malaria disease and transmission. Research and development in this field has been an area of intense effort by many groups over the last few decades. Despite this, there is currently no licensed malaria vaccine. Researchers, clinical trialists and vaccine developers have been working on many approached to make malaria vaccine available.African research institutions have developed and demonstrated a great capacity to undertake clinical trials in accordance to the International Conference on Harmonization-Good Clinical Practice (ICH-GCP) standards in the last decade; particularly in the field of malaria vaccines and anti-malarial drugs. This capacity is a result of networking among African scientists in collaboration with other partners; this has traversed both clinical trials and malaria control programmes as part of the Global Malaria Action Plan (GMAP). GMAP outlined and support global strategies toward the elimination and eradication of malaria in many areas, translating in reduction in public health burden, especially for African children. In the sub-Saharan region the capacity to undertake more clinical trials remains small in comparison to the actual need.However, sustainability of the already developed capacity is essential and crucial for the evaluation of different interventions and diagnostic tools/strategies for other diseases like TB, HIV, neglected tropical diseases and non-communicable diseases. There is urgent need for innovative mechanisms for the sustainability and expansion of the capacity in clinical trials in sub-Saharan Africa as the catalyst for health improvement and maintained.

  3. Questions and Answers about TB

    MedlinePlus

    ... Search Form Controls Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  4. Challenges and Future in Vaccines, Drug Development, and Immunomodulatory Therapy

    PubMed Central

    Nau, Gerard J.; Ross, Ted M.; Evans, Thomas G.; Chakraborty, Krishnendu; Empey, Kerry M.; Flynn, JoAnne L.

    2014-01-01

    Pulmonary diseases and infections are among the top contributors to human morbidity and mortality worldwide, and despite the successful history of vaccines and antimicrobial therapeutics, infectious disease still presents a significant threat to human health. Effective vaccines are frequently unavailable in developing countries, and successful vaccines have yet to be developed for major global maladies, such as tuberculosis. Furthermore, antibiotic resistance poses a growing threat to human health. The “Challenges and Future in Vaccines, Drug Development, and Immunomodulatory Therapy” session of the 2013 Pittsburgh International Lung Conference highlighted several recent and current studies related to treatment and prevention of antibiotic-resistant bacterial infections, highly pathogenic influenza, respiratory syncytial virus, and tuberculosis. Research presented here focused on novel antimicrobial therapies, new vaccines that are either in development or currently in clinical trials, and the potential for immunomodulatory therapies. These studies are making important contributions to the areas of microbiology, virology, and immunology related to pulmonary diseases and infections and are paving the way for improvements in the efficacy of vaccines and antimicrobials. PMID:25148426

  5. Challenges and future in vaccines, drug development, and immunomodulatory therapy.

    PubMed

    Kling, Heather M; Nau, Gerard J; Ross, Ted M; Evans, Thomas G; Chakraborty, Krishnendu; Empey, Kerry M; Flynn, JoAnne L

    2014-08-01

    Pulmonary diseases and infections are among the top contributors to human morbidity and mortality worldwide, and despite the successful history of vaccines and antimicrobial therapeutics, infectious disease still presents a significant threat to human health. Effective vaccines are frequently unavailable in developing countries, and successful vaccines have yet to be developed for major global maladies, such as tuberculosis. Furthermore, antibiotic resistance poses a growing threat to human health. The "Challenges and Future in Vaccines, Drug Development, and Immunomodulatory Therapy" session of the 2013 Pittsburgh International Lung Conference highlighted several recent and current studies related to treatment and prevention of antibiotic-resistant bacterial infections, highly pathogenic influenza, respiratory syncytial virus, and tuberculosis. Research presented here focused on novel antimicrobial therapies, new vaccines that are either in development or currently in clinical trials, and the potential for immunomodulatory therapies. These studies are making important contributions to the areas of microbiology, virology, and immunology related to pulmonary diseases and infections and are paving the way for improvements in the efficacy of vaccines and antimicrobials.

  6. Development of vaccines for Plasmodium vivax malaria.

    PubMed

    Mueller, Ivo; Shakri, Ahmad Rushdi; Chitnis, Chetan E

    2015-12-22

    Plasmodium vivax continues to cause significant morbidity outside Africa with more than 50% of malaria cases in many parts of South and South-east Asia, Pacific islands, Central and South America being attributed to P. vivax infections. The unique biology of P. vivax, including its ability to form latent hypnozoites that emerge months to years later to cause blood stage infections, early appearance of gametocytes before clinical symptoms are apparent and a shorter development cycle in the vector makes elimination of P. vivax using standard control tools difficult. The availability of an effective vaccine that provides protection and prevents transmission would be a valuable tool in efforts to eliminate P. vivax. Here, we review the latest developments related to P. vivax malaria vaccines and discuss the challenges as well as directions toward the goal of developing highly efficacious vaccines against P. vivax malaria. Copyright © 2015. Published by Elsevier Ltd.

  7. Development of a chimeric Zika vaccine using a licensed live-attenuated flavivirus vaccine as backbone.

    PubMed

    Li, Xiao-Feng; Dong, Hao-Long; Wang, Hong-Jiang; Huang, Xing-Yao; Qiu, Ye-Feng; Ji, Xue; Ye, Qing; Li, Chunfeng; Liu, Yang; Deng, Yong-Qiang; Jiang, Tao; Cheng, Gong; Zhang, Fu-Chun; Davidson, Andrew D; Song, Ya-Jun; Shi, Pei-Yong; Qin, Cheng-Feng

    2018-02-14

    The global spread of Zika virus (ZIKV) and its unexpected association with congenital defects necessitates the rapid development of a safe and effective vaccine. Here we report the development and characterization of a recombinant chimeric ZIKV vaccine candidate (termed ChinZIKV) that expresses the prM-E proteins of ZIKV using the licensed Japanese encephalitis live-attenuated vaccine SA14-14-2 as the genetic backbone. ChinZIKV retains its replication activity and genetic stability in vitro, while exhibiting an attenuation phenotype in multiple animal models. Remarkably, immunization of mice and rhesus macaques with a single dose of ChinZIKV elicits robust and long-lasting immune responses, and confers complete protection against ZIKV challenge. Significantly, female mice immunized with ChinZIKV are protected against placental and fetal damage upon ZIKV challenge during pregnancy. Overall, our study provides an alternative vaccine platform in response to the ZIKV emergency, and the safety, immunogenicity, and protection profiles of ChinZIKV warrant further clinical development.

  8. HIV and Tuberculosis (TB)

    MedlinePlus

    ... or brain. If not treated, TB disease can cause death. HIV weakens the immune system , increasing the risk ... spine, or brain. If not treated, TB can cause death. How does TB spread from person to person? ...

  9. Development of nonhuman adenoviruses as vaccine vectors

    PubMed Central

    Bangari, Dinesh S.; Mittal, Suresh K.

    2006-01-01

    Human adenoviral (HAd) vectors have demonstrated great potential as vaccine vectors. Preclinical and clinical studies have demonstrated the feasibility of vector design, robust antigen expression and protective immunity using this system. However, clinical use of adenoviral vectors for vaccine purposes is anticipated to be limited by vector immunity that is either preexisting or develops rapidly following the first inoculation with adenoviral vectors. Vector immunity inactivates the vector particles and rapidly removes the transduced cells, thereby limiting the duration of transgene expression. Due to strong vector immunity, subsequent use of the same vector is usually less efficient. In order to circumvent this limitation, nonhuman adenoviral vectors have been proposed as alternative vectors. In addition to eluding HAd immunity, these vectors possess most of the attractive features of HAd vectors. Several replication-competent or replication-defective nonhuman adenoviral vectors have been developed and investigated for their potential as vaccine delivery vectors. Here, we review recent advances in the design and characterization of various nonhuman adenoviral vectors, and discuss their potential applications for human and animal vaccination. PMID:16297508

  10. TB Summit 2014

    PubMed Central

    Maitra, Arundhati; Bhakta, Sanjib

    2014-01-01

    World TB Day commemorates Dr Robert Koch’s first announcement on March 24, 1882, that the bacterium Mycobacterium tuberculosis is the causative agent of tuberculosis. Currently, the event comprises of several conferences, meetings and activities held all over the world with the singular intention of raising public awareness about the global health emergency. In spite of having discovered the etiological agent of tuberculosis more than a century ago, a sizeable population still contract the disease every year and fall prey to it. In 2012, an estimated 8.6 million people developed the disease with 1.3 million succumbing to it. The number of TB deaths in children is unacceptably large, given that most are preventable. However, the challenge appears to be shifting toward attempts to control the rise and spread of the drug resistant variants of the microbe. To achieve this, a concerted effort from academia, clinical practice, and industry has been put forth. The TB Summit 2014 attempted to raise awareness as well as bring together experts involved in different aspects of tuberculosis research to help establish a more collective approach to battle this age-old disease. PMID:25003368

  11. Protein Crystallography in Vaccine Research and Development.

    PubMed

    Malito, Enrico; Carfi, Andrea; Bottomley, Matthew J

    2015-06-09

    The use of protein X-ray crystallography for structure-based design of small-molecule drugs is well-documented and includes several notable success stories. However, it is less well-known that structural biology has emerged as a major tool for the design of novel vaccine antigens. Here, we review the important contributions that protein crystallography has made so far to vaccine research and development. We discuss several examples of the crystallographic characterization of vaccine antigen structures, alone or in complexes with ligands or receptors. We cover the critical role of high-resolution epitope mapping by reviewing structures of complexes between antigens and their cognate neutralizing, or protective, antibody fragments. Most importantly, we provide recent examples where structural insights obtained via protein crystallography have been used to design novel optimized vaccine antigens. This review aims to illustrate the value of protein crystallography in the emerging discipline of structural vaccinology and its impact on the rational design of vaccines.

  12. Protein Crystallography in Vaccine Research and Development

    PubMed Central

    Malito, Enrico; Carfi, Andrea; Bottomley, Matthew J.

    2015-01-01

    The use of protein X-ray crystallography for structure-based design of small-molecule drugs is well-documented and includes several notable success stories. However, it is less well-known that structural biology has emerged as a major tool for the design of novel vaccine antigens. Here, we review the important contributions that protein crystallography has made so far to vaccine research and development. We discuss several examples of the crystallographic characterization of vaccine antigen structures, alone or in complexes with ligands or receptors. We cover the critical role of high-resolution epitope mapping by reviewing structures of complexes between antigens and their cognate neutralizing, or protective, antibody fragments. Most importantly, we provide recent examples where structural insights obtained via protein crystallography have been used to design novel optimized vaccine antigens. This review aims to illustrate the value of protein crystallography in the emerging discipline of structural vaccinology and its impact on the rational design of vaccines. PMID:26068237

  13. Accuracy of the QuantiFERON-TB Gold in Tube for diagnosing tuberculosis in a young pediatric population previously vaccinated with Bacille Calmette-Guérin

    PubMed Central

    Vallada, Marcelo Genofre; Okay, Thelma Suely; Del Negro, Gilda Maria B.; Antonio, Claudio Amaral; Yamamoto, Lidia; Ramos, Sonia Regina T. S.

    2014-01-01

    Objective: To evaluate the accuracy of an interferongamma release assay (QuantiFERON-TB Gold in Tube) for diagnosing Mycobacterium tuberculosis infection in a young pediatric population. Methods: 195 children previously vaccinated with BCG were evaluated, being 184 healthy individuals with no clinical or epidemiological evidence of mycobacterial infection, and 11 with Mycobacterium tuberculosis infection, according to clinical, radiological, and laboratory parameters. A blood sample was obtained from each child and processed according to the manufacturer's instructions. The assay performance was evaluated by a Receiver Operating Characteristic (ROC) curve. Results: In the group of 184 non-infected children, 130 (70.6%) were under the age of four years (mean age of 35 months). In this group, 177 children (96.2%) had negative test results, six (3.2%) had indeterminate results, and one (0.5%) had a positive result. In the group of 11 infected children, the mean age was 58.5 months, and two of them (18%) had negative results. The ROC curve had an area under the curve of 0.88 (95%CI 0.82-0.92; p<0.001), disclosing a predictive positive value of 81.8% for the test (95%CI 46.3-97.4). The assay sensitivity was 81.8% (95%CI 48.2-97.2) and the specificity was 98.8% (95%CI 96-99.8). Conclusions: In the present study, the QuantiFERON-TB Gold in Tube performance for diagnosing M. tuberculosis infection was appropriate in a young pediatric population. PMID:24676183

  14. Vaccines to prevent pneumonia in children - a developing country perspective.

    PubMed

    Oliwa, Jacquie N; Marais, Ben J

    2017-03-01

    Pneumonia accounted for 15% of the 6.3 million deaths among children younger than five years in 2013, a total of approximately 935,000 deaths worldwide. Routine vaccination against common childhood illnesses has been identified as one of the most cost-effective strategies to prevent death from pneumonia. Vaccine-preventable or potentially preventable diseases commonly linked with respiratory tract infections include Streptococcus pneumoniae, Haemophilus influenza type-b (Hib), pertussis, influenza, measles, and tuberculosis. Although here have been great strides in the development and administration of effective vaccines, the countries that carry the largest disease burdens still struggle to vaccinate their children and newer conjugated vaccines remain out of reach for many. The Global Vaccine Action Plan (GVAP) has identified priority areas for innovation in research in all aspects of immunisation development and delivery to ensure equitable access to vaccines for all. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Scientific challenges and opportunities in developing novel vaccines for the emerging and developing markets: New Technologies in Emerging Markets, October 16th-18th 2012, World Vaccine Congress, Lyon.

    PubMed

    Kochhar, Sonali

    2013-04-01

    Vaccines have had a major role in enhancing the quality of life and increasing life expectancy. Despite these successes and the development of new vaccine technologies, there remain multiple infectious diseases including AIDS, malaria and tuberculosis that require effective prophylactic vaccines. New and traditional technologies have a role in the development and delivery of the new vaccine candidates. The scientific challenges, opportunities and funding models for developing vaccines for low resource settings are highlighted here.

  16. Development of the PANVAC-VF vaccine for pancreatic cancer.

    PubMed

    Petrulio, Christian A; Kaufman, Howard L

    2006-02-01

    PANVAC-VF is a vaccine regimen composed of a priming dose of recombinant vaccinia virus and booster doses of recombinant fowlpox virus expressing carcinoembryonic antigen, mucin-1 and a triad of costimulatory molecules (TRICOM), which include B7.1, intercellular adhesion molecule-1 and leukocyte function-associated antigen-3. Vaccination is administered by subcutaneous injection followed by 4 days of local recombinant adjuvant granulocyte-macrophage colony-stimulating factor at the vaccination site. The vaccine has been developed for patients with advanced pancreatic cancer and has now entered a randomized Phase III clinical trial. This review will describe the background of recombinant poxvirus technology for tumor vaccine development, detail the key preclinical studies supporting the regimen, review the clinical trials supporting the current Phase III study, and highlight the key challenges and future obstacles to successful implementation of PANVAC-VF for pancreatic cancer.

  17. 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™.

  18. Middle East respiratory syndrome: obstacles and prospects for vaccine development

    PubMed Central

    Papaneri, Amy B.; Johnson, Reed F.; Wada, Jiro; Bollinger, Laura; Jahrling, Peter B.; Kuhn, Jens H.

    2016-01-01

    Summary The recent emergence of Middle East respiratory syndrome (MERS) highlights the need to engineer new methods for expediting vaccine development against emerging diseases. However, several obstacles prevent pursuit of a licensable MERS vaccine. First, the lack of a suitable animal model for MERS complicates in vivo testing of candidate vaccines. Second, due to the low number of MERS cases, pharmaceutical companies have little incentive to pursue MERS vaccine production as the costs of clinical trials are high. In addition, the timeline from bench research to approved vaccine use is 10 years or longer. Using novel methods and cost-saving strategies, genetically engineered vaccines can be produced quickly and cost-effectively. Along with progress in MERS animal model development, these obstacles can be circumvented or at least mitigated. PMID:25864502

  19. Design of clinical trials for therapeutic cancer vaccines development.

    PubMed

    Mackiewicz, Jacek; Mackiewicz, Andrzej

    2009-12-25

    Advances in molecular and cellular biology as well as biotechnology led to definition of a group of drugs referred to as medicinal products of advanced technologies. It includes gene therapy products, somatic cell therapeutics and tissue engineering. Therapeutic cancer vaccines including whole cell tumor cells vaccines or gene modified whole cells belong to somatic therapeutics and/or gene therapy products category. The drug development is a multistep complex process. It comprises of two phases: preclinical and clinical. Guidelines on preclinical testing of cell based immunotherapy medicinal products have been defined by regulatory agencies and are available. However, clinical testing of therapeutic cancer vaccines is still under debate. It presents a serious problem since recently clinical efficacy of the number of cancer vaccines has been demonstrated that focused a lot of public attention. In general clinical testing in the current form is very expensive, time consuming and poorly designed what may lead to overlooking of products clinically beneficial for patients. Accordingly regulatory authorities and researches including Cancer Vaccine Clinical Trial Working Group proposed three regulatory solutions to facilitate clinical development of cancer vaccines: cost-recovery program, conditional marketing authorization, and a new development paradigm. Paradigm includes a model in which cancer vaccines are investigated in two types of clinical trials: proof-of-principle and efficacy. The proof-of-principle trial objectives are: safety; dose selection and schedule of vaccination; and demonstration of proof-of-principle. Efficacy trials are randomized clinical trials with objectives of demonstrating clinical benefit either directly or through a surrogate. The clinical end points are still under debate.

  20. Recent advances in the development of vaccines against ricin.

    PubMed

    Brey, Robert N; Mantis, Nicholas J; Pincus, Seth H; Vitetta, Ellen S; Smith, Leonard A; Roy, Chad J

    2016-05-03

    Several promising subunit vaccines against ricin toxin (RT) have been developed during the last decade and are now being tested for safety and immunogenicity in humans and for efficacy in nonhuman primates. The incentive to develop a preventive vaccine as a countermeasure against RT use as a bioweapon is based on the high toxicity of RT after aerosol exposure, its environmental stability, abundance, and ease of purification. RT is the second most lethal biological toxin and is considered a "universal toxin" because it can kill all eukaryotic cells through binding to ubiquitous cell surface galactosyl residues. RT has two subunits conjoined by a single disulfide linkage: RTB, which binds galactosyl residues and RTA which enzymatically inactivates ribosomes intracellularly by cleavage ribosomal RNA. Attenuation of toxicity by elimination of the active site or introduction of other structural mutations of RTA has generated two similar clinical subunit vaccine candidates which induce antibodies in both humans and nonhuman primates. In rhesus macaques, inhaled RT causes rapid lung necrosis and fibrosis followed by death. After parenteral vaccination with RTA vaccine, macaques can be protected against aerosol RT exposure, suggesting that circulating antibodies can protect lung mucosa. Vaccination induces RT-neutralizing antibodies, the most likely correlate of protection. Macaques responded to conformational determinants in an RTA vaccine formulation, indicating preservation of RTA structure during initial manufacture. Comparative mapping studies have also demonstrated that macaques and humans recognize the same epitopes, significant in the study of macaques as a model during development of vaccines which cannot be tested for efficacy in humans.

  1. New developments in flavivirus vaccines with special attention to yellow fever.

    PubMed

    Pugachev, Konstantin V; Guirakhoo, Farshad; Monath, Thomas P

    2005-10-01

    Here we review recent epidemiological trends in flavivirus diseases, findings related to existing vaccines, and new directions in flavivirus vaccine research. We emphasize the need for stepped-up efforts to stop further spread and intensification of these infections worldwide. Although the incidence and geographic distribution of flavivirus diseases have increased in recent years, human vaccines are available only for yellow fever, Japanese encephalitis, tick-borne encephalitis and Kyasanur forest disease. Factors contributing to resurgence include insufficient supplies of available vaccines, incomplete vaccination coverage and relaxation in vector control. Research has been underway for 60 years to develop effective vaccines against dengue, and recent progress is encouraging. The development of vaccines against West Nile, virus recently introduced to North America, has been initiated. In addition, there is considerable interest in improving existing vaccines with respect to increasing safety (e.g. eliminating the newly recognized syndrome of yellow fever vaccine-associated viscerotropic adverse disease), and to reducing the cost and number of doses required for effective immunization. Traditional approaches to flavivirus vaccines are still employed, while recent advancements in biotechnology produced new approaches to vaccine design, such as recombinant live virus, subunit and DNA vaccines. Live chimeric vaccines against dengue, Japanese encephalitis and West Nile based on yellow fever 17D virus (ChimeriVax) are in phase I/II trials, with encouraging results. Other chimeric dengue, tick-borne encephalitis and West Nile virus candidates were developed based on attenuated dengue backbones. To further reduce the impact of flavivirus diseases, vaccination policies and vector control programs in affected countries require revision.

  2. Difference Between Latent TB Infection and Active TB Disease

    MedlinePlus

    ... chest x-ray, or positive sputum smear or culture • • Has active TB bacteria in his/her body • • Usually feels sick and may have symptoms such as coughing, fever, and weight loss • • May spread TB bacteria to others • • Needs treatment ...

  3. Development of Newborn and Infant Vaccines

    PubMed Central

    Sanchez-Schmitz, Guzman; Levy, Ofer

    2014-01-01

    Vaccines for early-life immunization are a crucial biomedical intervention to reduce global morbidity and mortality, yet their developmental path has been largely ad hoc, empiric, and inconsistent. Immune responses of human newborns and infants are distinct and cannot be predicted from those of human adults or animal models. Therefore, understanding and modeling age-specific human immune responses will be vital to the rational design and development of safe and effective vaccines for newborns and infants. PMID:21734174

  4. Mycobacterium tuberculosis region of difference (RD) 2 antigen Rv1985c and RD11 antigen Rv3425 have the promising potential to distinguish patients with active tuberculosis from M. bovis BCG-vaccinated individuals.

    PubMed

    Wang, Sen; Chen, Jiazhen; Zhang, Ying; Diao, Ni; Zhang, Shu; Wu, Jing; Lu, Chanyi; Wang, Feifei; Gao, Yan; Shao, Lingyun; Jin, Jialin; Weng, Xinhua; Zhang, Wenhong

    2013-01-01

    Antigens encoded in the region of difference (RD) of Mycobacterium tuberculosis constitute a potential source of specific immunodiagnostic antigens for distinguishing tuberculosis (TB) infection from BCG vaccination. We evaluated the diagnostic potential of specific T-cell epitopes selected from two immunodominant antigens, Rv1985c and Rv3425, from RD2 and RD11, respectively, on the basis of epitope mapping, in TB patients and BCG-vaccinated healthy individuals. Using a whole-blood gamma interferon release assay, a wide array of epitopes was recognized on both Rv1985c and Rv3425 in TB patients. Those epitopes that could specifically discriminate TB infection from BCG vaccination were carefully selected, and the most promising peptide pools from Rv1985c showed a sensitivity of 53.9% and a specificity of 95.5%. When the novel specific peptides from Rv1985c joined the diagnostic antigens in the QuantiFERON-TB Gold In-Tube (QFT-IT) assay, the sensitivity was increased from 86.4% to 96.2%, with no drop in specificity. These results indicate that the peptide pools selected from Rv1985c and Rv3425 have the potential to diagnose TB infection by a method that may be routinely used in clinical laboratories.

  5. Cross-stage immunity for malaria vaccine development.

    PubMed

    Nahrendorf, Wiebke; Scholzen, Anja; Sauerwein, Robert W; Langhorne, Jean

    2015-12-22

    A vaccine against malaria is urgently needed for control and eventual eradication. Different approaches are pursued to induce either sterile immunity directed against pre-erythrocytic parasites or to mimic naturally acquired immunity by controlling blood-stage parasite densities and disease severity. Pre-erythrocytic and blood-stage malaria vaccines are often seen as opposing tactics, but it is likely that they have to be combined into a multi-stage malaria vaccine to be optimally safe and effective. Since many antigenic targets are shared between liver- and blood-stage parasites, malaria vaccines have the potential to elicit cross-stage protection with immune mechanisms against both stages complementing and enhancing each other. Here we discuss evidence from pre-erythrocytic and blood-stage subunit and whole parasite vaccination approaches that show that protection against malaria is not necessarily stage-specific. Parasites arresting at late liver-stages especially, can induce powerful blood-stage immunity, and similarly exposure to blood-stage parasites can afford pre-erythrocytic immunity. The incorporation of a blood-stage component into a multi-stage malaria vaccine would hence not only combat breakthrough infections in the blood should the pre-erythrocytic component fail to induce sterile protection, but would also actively enhance the pre-erythrocytic potency of this vaccine. We therefore advocate that future studies should concentrate on the identification of cross-stage protective malaria antigens, which can empower multi-stage malaria vaccine development. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Viral Vectors for Use in the Development of Biodefense Vaccines

    DTIC Science & Technology

    2005-06-17

    vaccinia virus, and Venezuelan equine encephalitis virus, as vaccine vectors has enabled researchers to develop effective means for countering the...biowarfare. The use of viruses, for example adenovirus, vaccinia virus, and Venezuelan equine encephalitis virus, as vaccine -vectors has enabled researchers to... vaccines . . . . . . . . . . . . . . . . . . . 1298 2.1.3. Vaccinia virus-vectored Venezuelan equine encephalitis vaccines

  7. Granulysin as a Correlate of Immune Response following Mycobacterial Infection

    USDA-ARS?s Scientific Manuscript database

    Correlates of protection following vaccination against TB are needed in the development of improved vaccines against TB. Evaluation of vaccine efficacy is based on measuring IFN gamma levels and antigen-specific proliferation. Granulysin is an antimicrobial protein expressed by T lymphocytes and NK ...

  8. Genome-based approaches to develop vaccines against bacterial pathogens.

    PubMed

    Serruto, Davide; Serino, Laura; Masignani, Vega; Pizza, Mariagrazia

    2009-05-26

    Bacterial infectious diseases remain the single most important threat to health worldwide. Although conventional vaccinology approaches were successful in conferring protection against several diseases, they failed to provide efficacious solutions against many others. The advent of whole-genome sequencing changed the way to think about vaccine development, enabling the targeting of possible vaccine candidates starting from the genomic information of a single bacterial isolate, with a process named reverse vaccinology. As the genomic era progressed, reverse vaccinology has evolved with a pan-genome approach and multi-strain genome analysis became fundamental for the design of universal vaccines. This review describes the applications of genome-based approaches in the development of new vaccines against bacterial pathogens.

  9. Candida vaccines development from point view of US patent application.

    PubMed

    Wang, Shyh-Jen

    2011-11-01

    Candidiasis is the fourth most common bloodstream infection in hospitalized patients in the United States. Moreover, the mortality rate from Candida infections remains high, even after treatment with antifungal therapy. Vaccination would be a promising strategy for prevention of invasive fungal infections. In order to examine the main trends in anticandidal vaccine patenting activity, we conducted an analysis for anticandidal vaccine patents. We find 190 issued patent and 940 patent application documents containing the keywords Candida and vaccine within claims in the USA. Candida vaccines development, as evidenced by the numbers of issued patents, has decreased since the year 2002. Furthermore, the number of patent applications in Candida vaccines may indicate the strength of engaged resources were also in the status of stagnation during 2005-2007 and even a decline in 2008. Academic and nonprofit research institutions not only account for a large share of Candida vaccines patents but also apply for patents continually. Based on this analysis, the strength of Candida vaccines resources seems to remain stagnant in recent years due to patent prosecution or technical barrier in the filed of Candida vaccines. Therefore, we consider that Candida vaccines technology to still be under development and the researchers are still looking for scientific breakthrough in the filed.

  10. Regulatory considerations for clinical development of cancer vaccines.

    PubMed

    Heelan, Bridget Theresa

    2014-01-01

    Cancer vaccines are aimed at stimulating an immune response to tumor tissue. There is a high level of clinical activity in this rapidly advancing field with over 1,400 trials registered on Clincaltrials.gov. The recent approval of Sipuleucel-T which is the first cancer vaccine approved in the US and EU has encouraged developers in this field. In contrast to more established approaches for treating cancer such as chemotherapy, regulatory guidelines have been developed relatively recently for cancer vaccines. These guidelines advise on general clinical requirements. As there is an increase in innovative strategies with novel products, a 2-way dialog with regulators is recommended on a case-by-case basis to justify the clinical development plan, taking into account specific quality issues related to the product(s) in development. It is important that the rationale, background and justification for the planned development is convincing when interacting with the regulatory authorities, to enable drug developers and regulators to reach agreement.

  11. Development of replication-deficient adenovirus malaria vaccines.

    PubMed

    Hollingdale, Michael R; Sedegah, Martha; Limbach, Keith

    2017-03-01

    Malaria remains a major threat to endemic populations and travelers, including military personnel to these areas. A malaria vaccine is feasible, as radiation attenuated sporozoites induce nearly 100% efficacy. Areas covered: This review covers current malaria clinical trials using adenoviruses and pre-clinical research. Heterologous prime-boost regimens, including replication-deficient human adenovirus 5 (HuAd5) carrying malaria antigens, are efficacious. However, efficacy appears to be adversely affected by pre-existing anti-HuAd5 antibodies. Current strategies focus on replacing HuAd5 with rarer human adenoviruses or adenoviruses isolated from non-human primates (NHPs). The chimpanzee adenovirus ChAd63 is undergoing evaluation in clinical trials including infants in malaria-endemic areas. Key antigens have been identified and are being used alone, in combination, or with protein subunit vaccines. Gorilla adenoviruses carrying malaria antigens are also currently being evaluated in preclinical models. These replacement adenovirus vectors will be successfully used to develop vaccines against malaria, as well as other infectious diseases. Expert commentary: Simplified prime-boost single shot regimens, dry-coated live vector vaccines or silicon microneedle arrays could be developed for malaria or other vaccines. Replacement vectors with similar or superior immunogenicity have rapidly advanced, and several are now in extensive Phase 2 and beyond in malaria as well as other diseases, notably Ebola.

  12. Arenavirus reverse genetics for vaccine development

    PubMed Central

    Ortiz-Riaño, Emilio; Cheng, Benson Yee Hin; Carlos de la Torre, Juan

    2013-01-01

    Arenaviruses are important human pathogens with no Food and Drug Administration (FDA)-licensed vaccines available and current antiviral therapy being limited to an off-label use of the nucleoside analogue ribavirin of limited prophylactic efficacy. The development of reverse genetics systems represented a major breakthrough in arenavirus research. However, rescue of recombinant arenaviruses using current reverse genetics systems has been restricted to rodent cells. In this study, we describe the rescue of recombinant arenaviruses from human 293T cells and Vero cells, an FDA-approved line for vaccine development. We also describe the generation of novel vectors that mediate synthesis of both negative-sense genome RNA and positive-sense mRNA species of lymphocytic choriomeningitis virus (LCMV) directed by the human RNA polymerases I and II, respectively, within the same plasmid. This approach reduces by half the number of vectors required for arenavirus rescue, which could facilitate virus rescue in cell lines approved for human vaccine production but that cannot be transfected at high efficiencies. We have shown the feasibility of this approach by rescuing both the Old World prototypic arenavirus LCMV and the live-attenuated vaccine Candid#1 strain of the New World arenavirus Junín. Moreover, we show the feasibility of using these novel strategies for efficient rescue of recombinant tri-segmented both LCMV and Candid#1. PMID:23364194

  13. Receptor-binding domain as a target for developing SARS vaccines.

    PubMed

    Zhu, Xiaojie; Liu, Qi; Du, Lanying; Lu, Lu; Jiang, Shibo

    2013-08-01

    A decade ago, severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) caused a global pandemic with a mortality rate of 10%. Reports of recent outbreaks of a SARS-like disease caused by Middle East respiratory syndrome coronavirus (MERS-CoV) have raised serious concerns of a possible reemergence of SARS-CoV, either by laboratory escape or the presence of a natural reservoir. Therefore, the development of effective and safe SARS vaccines is still needed. Based on our previous studies, we believe that the receptor-binding domain (RBD) in the S1 subunit of the SARS-CoV spike (S) protein is the most important target for developing a SARS vaccine. In particular, RBD of S protein contains the critical neutralizing domain (CND), which is able to induce highly potent neutralizing antibody response and cross-protection against divergent SARS-CoV strains. Furthermore, a RBD-based subunit vaccine is expected to be safer than other vaccines that may induce Th2-type immunopathology. This review will discuss key advances in the development of RBD-based SARS vaccines and the possibility of using a similar strategy to develop vaccines against MERS-CoV.

  14. A proposed national strategy for tuberculosis vaccine development.

    PubMed

    Ginsberg, A M

    2000-06-01

    The global tuberculosis epidemic causes approximately 5% of deaths worldwide. Despite recent concerted and largely successful tuberculosis control efforts, the incidence of tuberculosis in the United States remains 74-fold higher than the stated elimination goal of <1 case per million population by the year 2010. Current bacille Calmette-Guérin vaccines, although efficacious in preventing extrapulmonary tuberculosis in young children, have shown widely variable efficacy in preventing adult pulmonary tuberculosis, confound skin test screening, and are not recommended for use in the United States. The Advisory Council for Elimination of Tuberculosis recently stated that tuberculosis would not be eliminated from the United States without a more effective vaccine. Recent scientific advances have created unprecedented opportunity for tuberculosis vaccine development. Therefore, members of the broad tuberculosis research and control communities have recently created and proposed a national strategy, or blueprint, for tuberculosis vaccine development, which is presented here.

  15. Yellow fever vector live-virus vaccines: West Nile virus vaccine development.

    PubMed

    Arroyo, J; Miller, C A; Catalan, J; Monath, T P

    2001-08-01

    By combining molecular-biological techniques with our increased understanding of the effect of gene sequence modification on viral function, yellow fever 17D, a positive-strand RNA virus vaccine, has been manipulated to induce a protective immune response against viruses of the same family (e.g. Japanese encephalitis and dengue viruses). Triggered by the emergence of West Nile virus infections in the New World afflicting humans, horses and birds, the success of this recombinant technology has prompted the rapid development of a live-virus attenuated candidate vaccine against West Nile virus.

  16. Vaccine safety monitoring systems in developing countries: an example of the Vietnam model.

    PubMed

    Ali, Mohammad; Rath, Barbara; Thiem, Vu Dinh

    2015-01-01

    Only few health intervention programs have been as successful as vaccination programs with respect to preventing morbidity and mortality in developing countries. However, the success of a vaccination program is threatened by rumors and misunderstanding about the risks of vaccines. It is short-sighted to plan the introduction of vaccines into developing countries unless effective vaccine safety monitoring systems are in place. Such systems that track adverse events following immunization (AEFI) is currently lacking in most developing countries. Therefore, any rumor may affect the entire vaccination program. Public health authorities should implement the safety monitoring system of vaccines, and disseminate safety issues in a proactive mode. Effective safety surveillance systems should allow for the conduct of both traditional and alternative epidemiologic studies through the use of prospective data sets. The vaccine safety data link implemented in Vietnam in mid-2002 indicates that it is feasible to establish a vaccine safety monitoring system for the communication of vaccine safety in developing countries. The data link provided the investigators an opportunity to evaluate AEFI related to measles vaccine. Implementing such vaccine safety monitoring system is useful in all developing countries. The system should be able to make objective and clear communication regarding safety issues of vaccines, and the data should be reported to the public on a regular basis for maintaining their confidence in vaccination programs.

  17. Mucosal immunity and novel tuberculosis vaccine strategies: route of immunisation-determined T-cell homing to restricted lung mucosal compartments.

    PubMed

    Lai, Rocky; Afkhami, Sam; Haddadi, Siamak; Jeyanathan, Mangalakumari; Xing, Zhou

    2015-06-01

    Despite the use of bacille Calmette-Guérin (BCG) for almost a century, pulmonary tuberculosis (TB) continues to be a serious global health concern. Therefore, there has been a pressing need for the development of new booster vaccines to enhance existing BCG-induced immunity. Protection following mucosal intranasal immunisation with AdHu5Ag85A is associated with the localisation of antigen-specific T-cells to the lung airway. However, parenteral intramuscular immunisation is unable to provide protection despite the apparent presence of antigen-specific T-cells in the lung interstitium. Recent advances in intravascular staining have allowed us to reassess the previously established T-cell distribution profile and its relationship with the observed differential protection. Respiratory mucosal immunisation empowers T-cells to home to both the lung interstitium and the airway lumen, whereas intramuscular immunisation-activated T-cells are largely trapped within the pulmonary vasculature, unable to populate the lung interstitium and airway. Given the mounting evidence supporting the safety and enhanced efficacy of respiratory mucosal immunisation over the traditional parenteral immunisation route, a greater effort should be made to clinically develop respiratory mucosal-deliverable TB vaccines. Copyright ©ERS 2015.

  18. Drug permeation and metabolism in Mycobacterium tuberculosis: Prioritising local exposure as essential criterion in new TB drug development.

    PubMed

    Tanner, Lloyd; Denti, Paolo; Wiesner, Lubbe; Warner, Digby F

    2018-06-22

    Anti-tuberculosis (TB) drugs possess diverse abilities to penetrate the different host tissues and cell types in which infecting Mycobacterium tuberculosis bacilli are located during active disease. This is important since there is increasing evidence that the respective "lesion-penetrating" properties of the front-line TB drugs appear to correlate well with their specific activity in standard combination therapy. In turn, these observations suggest that rational efforts to discover novel treatment-shortening drugs and drug combinations should incorporate knowledge about the comparative abilities of both existing and experimental anti-TB agents to access bacilli in defined physiological states at different sites of infection, as well as avoid elimination by efflux or inactivation by host or bacterial metabolism. However, while there is a fundamental requirement to understand the mode of action and pharmacological properties of any current or experimental anti-TB agent within the context of the obligate human host, this is complex and, until recently, has been severely limited by the available methodologies and models. Here, we discuss advances in analytical models and technologies which have enabled investigations of drug metabolism and pharmacokinetics (DMPK) for new TB drug development. In particular, we consider the potential to shift the focus of traditional pharmacokinetic-pharmacodynamic analyses away from plasma to a more specific "site of action" drug exposure as an essential criterion for drug development and the design of dosing strategies. Moreover, in summarising approaches to determine DMPK data for the "unit of infection" comprising host macrophage and intracellular bacillus, we evaluate the potential benefits of including these analyses at an early stage in the preclinical drug development algorithm. © 2018 IUBMB Life, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

  19. Helminth Coinfection Does Not Affect Therapeutic Effect of a DNA Vaccine in Mice Harboring Tuberculosis

    PubMed Central

    Frantz, Fabiani G.; Rosada, Rogério S.; Peres-Buzalaf, Camila; Perusso, Franciele R. T.; Rodrigues, Vanderlei; Ramos, Simone G.; Kunkel, Steven L.; Silva, Célio L.; Faccioli, Lúcia H.

    2010-01-01

    Background Helminthiasis and tuberculosis (TB) coincide geographically and there is much interest in exploring how concurrent worm infections might alter immune responses against bacilli and might necessitate altered therapeutic approaches. A DNA vaccine that codifies heat shock protein Hsp65 from M. leprae (DNAhsp65) has been used in therapy during experimental tuberculosis. This study focused on the impact of the co-existence of worms and TB on the therapeutic effects of DNAhsp65. Methodology/Principal Findings Mice were infected with Toxocara canis or with Schistosoma mansoni, followed by coinfection with M. tuberculosis and treatment with DNAhsp65. While T. canis infection did not increase vulnerability to pulmonary TB, S. mansoni enhanced susceptibility to TB as shown by higher numbers of bacteria in the lungs and spleen, which was associated with an increase in Th2 and regulatory cytokines. However, in coinfected mice, the therapeutic effect of DNAhsp65 was not abrogated, as indicated by colony forming units and analysis of histopathological changes. In vitro studies indicated that Hsp65-specific IFN-γ production was correlated with vaccine-induced protection in coinfected mice. Moreover, in S. mansoni-coinfected mice, DNA treatment inhibited in vivo TGF-β and IL-10 production, which could be associated with long-term protection. Conclusions/Significance We have demonstrated that the therapeutic effects of DNAhsp65 in experimental TB infection are persistent in the presence of an unrelated Th2 immune response induced by helminth infections. PMID:20544012

  20. [The development of therapeutic vaccine for hepatitis C virus].

    PubMed

    Kimura, Kiminori; Kohara, Michinori

    2012-10-01

    Chronic hepatitis C caused by infection with the hepatitis C virus(HCV)is a global health problem. HCV causes persistent infection that can lead to chronic liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. The therapeutic efficacy of antiviral drugs is not optimal in patients with chronic infection; furthermore, an effective vaccine has not yet been developed. To design an effective HCV vaccine, generation of a convenient animal model of HCV infection is necessary. Recently, we used the Cre/loxP switching system to generate an immunocompetent mouse model of HCV expression, thereby enabling the study of host immune responses against HCV proteins. At present vaccine has not yet been shown to be therapeutically effective against chronic HCV infection. We examined the therapeutic effects of a recombinant vaccinia virus(rVV)encoding HCV protein in a mouse model. we generated rVVs for 3 different HCV proteins and found that one of the recombinant viruses encoding a nonstructural protein(rVV-N25)resolved pathological chronic hepatitis C symptoms in the liver. We propose the possibility that rVV-N25 immunization has the potential for development of an effective therapeutic vaccine for HCV induced chronic hepatitis. The utilization of the therapeutic vaccine can protect progress to chronic hepatitis, and as a consequence, leads to eradication of hepatocellular carcinoma. In this paper, we summarized our current study for HCV therapeutic vaccine and review the vaccine development to date.

  1. Preclinical development of BCG.HIVA2auxo.int, harboring an integrative expression vector, for a HIV-TB Pediatric vaccine. Enhancement of stability and specific HIV-1 T-cell immunity.

    PubMed

    Mahant, Aakash; Saubi, Narcís; Eto, Yoshiki; Guitart, Núria; Gatell, Josep Ma; Hanke, Tomáš; Joseph, Joan

    2017-08-03

    One of the critical issues that should be addressed in the development of a BCG-based HIV vaccine is genetic plasmid stability. Therefore, to address this issue we have considered using integrative vectors and the auxotrophic mutant of BCG complemented with a plasmid carrying a wild-type complementing gene. In this study, we have constructed an integrative E. coli-mycobacterial shuttle plasmid, p2auxo.HIVA int , expressing the HIV-1 clade A immunogen HIVA. This shuttle vector uses an antibiotic resistance-free mechanism for plasmid selection and maintenance. It was first transformed into a glycine auxotrophic E. coli strain and subsequently transformed into a lysine auxotrophic Mycobacterium bovis BCG strain to generate the vaccine BCG.HIVA 2auxo.int . Presence of the HIVA gene sequence and protein expression was confirmed. We demonstrated that the in vitro stability of the integrative plasmid p2auxo.HIVA int was increased 4-fold, as compared with the BCG strain harboring the episomal plasmid, and was genetically and phenotypically characterized. The BCG.HIVA 2auxo.int vaccine in combination with modified vaccinia virus Ankara (MVA).HIVA was found to be safe and induced HIV-1 and Mycobacterium tuberculosis-specific interferon-γ-producing T-cell responses in adult BALB/c mice. We have engineered a more stable and immunogenic BCG-vectored vaccine using the prototype immunogen HIVA. Thus, the use of integrative expression vectors and the antibiotic-free plasmid selection system based on "double" auxotrophic complementation are likely to improve the mycobacterial vaccine stability in vivo and immunogenicity to develop not only recombinant BCG-based vaccines expressing second generation of HIV-1 immunogens but also other major pediatric pathogens to prime protective responses shortly following birth.

  2. Staying on Track with TB Medicine

    MedlinePlus

    ... medicines. If you have TB disease , you must remember that TB germs die very slowly. Even if you feel better after a few weeks on the TB medicines, it does not mean all the TB germs are dead. Treating TB takes months. Staying on your medicine the ... points to remember: • Anyone can breathe in TB germs and get ...

  3. [Development of current smallpox vaccines].

    PubMed

    Maksiutov, R A; Gavrilova, E V; Shchelkunov, S N

    2011-01-01

    The review gives data on the history of smallpox vaccination and shows the high topicality of designing the current safe vaccines against orthopoxviruses. Four generations of live smallpox, protein subunit, and DNA vaccines are considered. Analysis of the data published leads to the conclusion that it is promising to use the up-to-date generations of safe smallpox subunit or DNA vaccines for mass primary immunization with possible further revaccination with classical live vaccine.

  4. Tuberculosis Facts - TB and HIV/AIDS

    MedlinePlus

    Tuberculosis (TB) Facts TB and HIV/AIDS What is TB? “TB” is short for a disease called tuberculosis. TB is spread through the air from one ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination

  5. A review of vaccine development and research for industry animals in Korea

    PubMed Central

    Lee, Nak-Hyung; Lee, Jung-Ah; Park, Seung-Yong; Song, Chang-Seon; Choi, In-Soo

    2012-01-01

    Vaccination has proven to be the most cost-effective strategy for controlling a wide variety of infectious diseases in humans and animals. For the last decade, veterinary vaccines have been substantially developed and demonstrated their effectiveness against many diseases. Nevertheless, new vaccines are greatly demanded to effectively control newly- and re-emerging pathogens in livestock. However, development of veterinary vaccines is a challenging task, in part, due to a variety of pathogens, hosts, and the uniqueness of host-susceptibility to each pathogen. Therefore, novel concepts of vaccines should be explored to overcome the limitation of conventional vaccines. There have been greatly advanced in the completion of genomic sequencing of pathogens, the application of comparative genomic and transcriptome analysis. This would facilitate to open opportunities up to investigate a new generation of vaccines; recombinant subunit vaccine, virus-like particle, DNA vaccine, and vector-vehicle vaccine. Currently, such types of vaccines are being actively explored against various livestock diseases, affording numerous advantages over conventional vaccines, including ease of production, immunogenicity, safety, and multivalency in a single shot. In this articles, the authors present the current status of the development of veterinary vaccines at large as well as research activities conducted in Korea. PMID:23596575

  6. Ebola hemorrhagic Fever and the current state of vaccine development.

    PubMed

    Hong, Joo Eun; Hong, Kee-Jong; Choi, Woo Young; Lee, Won-Ja; Choi, Yeon Hwa; Jeong, Chung-Hyeon; Cho, Kwang-Il

    2014-12-01

    Current Ebola virus outbreak in West Africa already reached the total number of 1,323 including 729 deaths by July 31st. the fatality is around 55% in the southeastern area of Guinea, Sierra Leone, Liberia, and Nigeria. The number of patients with Ebola Hemorrhagic Fever (EHF) was continuously increasing even though the any effective therapeutics or vaccines has not been developed yet. The Ebola virus in Guinea showed 98% homology with Zaire Ebola Virus. Study of the pathogenesis of Ebola virus infection and assess of the various candidates of vaccine have been tried for a long time, especially in United States and some European countries. Even though the attenuated live vaccine and DNA vaccine containing Ebola viral genes were tested and showed efficacy in chimpanzees, those candidates still need clinical tests requiring much longer time than the preclinical development to be approved for the practical treatment. It can be expected to eradicate Ebola virus by a safe and efficient vaccine development similar to the case of smallpox virus which was extinguished from the world by the variola vaccine.

  7. Status of research and development of vaccines for Streptococcus pyogenes.

    PubMed

    Steer, Andrew C; Carapetis, Jonathan R; Dale, James B; Fraser, John D; Good, Michael F; Guilherme, Luiza; Moreland, Nicole J; Mulholland, E Kim; Schodel, Florian; Smeesters, Pierre R

    2016-06-03

    Streptococcus pyogenes is an important global pathogen, causing considerable morbidity and mortality, especially in low and middle income countries where rheumatic heart disease and invasive infections are common. There is a number of promising vaccine candidates, most notably those based on the M protein, the key virulence factor for the bacterium. Vaccines against Streptococcus pyogenes are considered as impeded vaccines because of a number of crucial barriers to development. Considerable effort is needed by key players to bring current vaccine candidates through phase III clinical trials and there is a clear need to develop a roadmap for future development of current and new candidates. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  8. Development of improved vaccines against whooping cough: current status.

    PubMed

    Marzouqi, Ibrahim; Richmond, Peter; Fry, Scott; Wetherall, John; Mukkur, Trilochan

    2010-07-01

    Prior to the introduction of killed whole cell pertussis vaccine [wP] in the 1940s, whooping cough was a major cause of infant death worldwide. Widespread vaccination of children with this vaccine caused a significant reduction in mortality. However in the 1990s and now more recently, there has been a resurgence of pertussis in several countries even in populations previously vaccinated with an acellular pertussis vaccine [aP]. In this review, we describe the epidemiology of whooping cough, the vast array of virulence factors produced by this pathogen potentially contributing to the resurgence of pertussis even in previously vaccinated populations of infants and children, history of whooping cough prophylaxis, possible mechanisms of immunity, lack of availability of a suitable non-toxic adjuvant capable of inducing both arms of the immune response, and the current status of development of improved vaccines with potential to induce longer-lasting protection, than is currently possible with the wP or aP vaccines, against whooping cough.

  9. Advances in neglected tropical disease vaccines: Developing relative potency and functional assays for the Na-GST-1/Alhydrogel hookworm vaccine

    PubMed Central

    Brelsford, Jill B.; Plieskatt, Jordan L.; Yakovleva, Anna; Jariwala, Amar; Keegan, Brian P.; Peng, Jin; Xia, Pengjun; Li, Guangzhao; Campbell, Doreen; Periago, Maria Victoria; Correa-Oliveira, Rodrigo; Bottazzi, Maria Elena; Hotez, Peter J.

    2017-01-01

    A new generation of vaccines for the neglected tropical diseases (NTDs) have now advanced into clinical development, with the Na-GST-1/Alhydrogel Hookworm Vaccine already being tested in Phase 1 studies in healthy adults. The current manuscript focuses on the often overlooked critical aspects of NTD vaccine product development, more specifically, vaccine stability testing programs. A key measure of vaccine stability testing is "relative potency" or the immunogenicity of the vaccine during storage. As with most NTD vaccines, the Na-GST-1/Alhydrogel Hookworm Vaccine was not developed by attenuation or inactivation of the pathogen (Necator americanus), so conventional methods for measuring relative potency are not relevant for this investigational product. Herein, we describe a novel relative potency testing program and report for the first time on the clinical lot of this NTD vaccine during its first 60 months of storage at 2–8°C. We also describe the development of a complementary functional assay that measures the ability of IgG from animals or humans immunized with Na-GST-1/Alhydrogel to neutralize this important hookworm enzyme. While 90% inhibition of the catalytic activity of Na-GST-1 was achieved in animals immunized with Na-GST-1/Alhydrogel, lower levels of inhibition were observed in immunized humans. Moreover, anti-Na-GST-1 antibodies from volunteers in non-hookworm endemic areas were better able to inhibit catalytic activity than anti-Na-GST-1 antibodies from volunteers resident in hookworm endemic areas. The results described herein provide the critical tools for the product development of NTD vaccines. PMID:28192438

  10. Advances in neglected tropical disease vaccines: Developing relative potency and functional assays for the Na-GST-1/Alhydrogel hookworm vaccine.

    PubMed

    Brelsford, Jill B; Plieskatt, Jordan L; Yakovleva, Anna; Jariwala, Amar; Keegan, Brian P; Peng, Jin; Xia, Pengjun; Li, Guangzhao; Campbell, Doreen; Periago, Maria Victoria; Correa-Oliveira, Rodrigo; Bottazzi, Maria Elena; Hotez, Peter J; Diemert, David; Bethony, Jeffrey M

    2017-02-01

    A new generation of vaccines for the neglected tropical diseases (NTDs) have now advanced into clinical development, with the Na-GST-1/Alhydrogel Hookworm Vaccine already being tested in Phase 1 studies in healthy adults. The current manuscript focuses on the often overlooked critical aspects of NTD vaccine product development, more specifically, vaccine stability testing programs. A key measure of vaccine stability testing is "relative potency" or the immunogenicity of the vaccine during storage. As with most NTD vaccines, the Na-GST-1/Alhydrogel Hookworm Vaccine was not developed by attenuation or inactivation of the pathogen (Necator americanus), so conventional methods for measuring relative potency are not relevant for this investigational product. Herein, we describe a novel relative potency testing program and report for the first time on the clinical lot of this NTD vaccine during its first 60 months of storage at 2-8°C. We also describe the development of a complementary functional assay that measures the ability of IgG from animals or humans immunized with Na-GST-1/Alhydrogel to neutralize this important hookworm enzyme. While 90% inhibition of the catalytic activity of Na-GST-1 was achieved in animals immunized with Na-GST-1/Alhydrogel, lower levels of inhibition were observed in immunized humans. Moreover, anti-Na-GST-1 antibodies from volunteers in non-hookworm endemic areas were better able to inhibit catalytic activity than anti-Na-GST-1 antibodies from volunteers resident in hookworm endemic areas. The results described herein provide the critical tools for the product development of NTD vaccines.

  11. [Overview of the Ebola vaccines in pre-clinical and clinical development].

    PubMed

    Buchy, P

    2016-10-01

    The Ebola epidemic that occurred in West Africa between 2013-2016 significantly accelerated the research and development of Ebola vaccines. Few dozens of clinical trials have been recently conducted leading to opportunities to test several new vaccine candidates. Other vaccines are still in early development phases (table 1). This paper provides an overview of the new developments in that area.

  12. Development and approval of vaccines in the United States.

    PubMed

    Botstein, P

    1986-01-01

    In the United States, vaccines and the establishments in which they are manufactured are required to be licensed by the Food and Drug Administration (FDA) before the vaccine can be marketed. This licensing process, as well as the development and investigation of vaccines, is regulated by the FDA's Office of Biologics Research and Review. An application for licensing must contain information supporting the safety, effectiveness, purity and potency of the product. These are data obtained during the investigational phase and then submitted by a commercial sponsor for review and approval. Inspections, surveillance and laboratory testing are performed by the FDA before and after issuance of a license for marketing. The procedures and policies in the investigational and licensing phases of vaccine development are described.

  13. Methods and Protocols for Developing Prion Vaccines.

    PubMed

    Marciniuk, Kristen; Taschuk, Ryan; Napper, Scott

    2016-01-01

    Prion diseases denote a distinct form of infectivity that is based in the misfolding of a self-protein (PrP(C)) into a pathological, infectious conformation (PrP(Sc)). Efforts to develop vaccines for prion diseases have been complicated by the potential dangers that are associated with induction of immune responses against a self-protein. As a consequence, there is considerable appeal for vaccines that specifically target the misfolded prion conformation. Such conformation-specific immunotherapy is made possible through the identification of vaccine targets (epitopes) that are exclusively presented as a consequence of misfolding. An immune response directed against these targets, termed disease-specific epitopes (DSEs), has the potential to spare the function of the native form of the protein while clearing, or neutralizing, the infectious isomer. Although identification of DSEs represents a critical first step in the induction of conformation-specific immune responses, substantial efforts are required to translate these targets into functional vaccines. Due to the poor immunogenicity that is inherent to self-proteins, and that is often associated with short peptides, substantial efforts are required to overcome tolerance-to-self and maximize the resultant immune response following DSE-based immunization. This often includes optimization of target sequences in terms of immunogenicity and development of effective formulation and delivery strategies for the associated peptides. Further, these vaccines must satisfy additional criteria from perspectives of specificity (PrP(C) vs. PrP(Sc)) and safety (antibody-induced template-driven misfolding of PrP(C)). The emphasis of this report is on the steps required to translate DSEs into prion vaccines and subsequent evaluation of the resulting immune responses.

  14. Development of replication-competent viral vectors for HIV vaccine delivery

    PubMed Central

    Parks, Christopher L.; Picker, Louis J.; King, C. Richter

    2014-01-01

    Purpose of review Briefly describe some of the replication-competent (RC) vectors being investigated for development of candidate HIV vaccines focusing primarily on technologies that have advanced to testing in macaques or have entered clinical trials. Recent findings RC viral vectors have advanced to the stage were decisions can be made regarding future development of HIV vaccines. The viruses being used as RC vector platforms vary considerably, and their unique attributes make it possible to test multiple vaccine design concepts and also mimic various aspects of an HIV infection. RC viral vectors encoding SIV or HIV proteins can be used to safely immunize macaques, and in some cases, there is evidence of significant vaccine efficacy in challenge protection studies. Several live HIV vaccine vectors are in clinical trials to evaluate immunogenicity, safety, the effect of mucosal delivery, and potential effects of pre-existing immunity. Summary A variety of DNA and RNA viruses are being used to develop RC viral vectors for HIV vaccine delivery. Multiple viral vector platforms have proven to be safe and immunogenic with evidence of efficacy in macaques. Some of the more advanced HIV vaccine prototypes based on vesicular stomatitis virus, vaccinia virus, measles virus, and Sendai virus are in clinical trials. PMID:23925000

  15. Development and clinical testing of multivalent vaccines based on a diphtheria-tetanus-acellular pertussis vaccine: difficulties encountered and lessons learned.

    PubMed

    Capiau, Carine; Poolman, Jan; Hoet, Bernard; Bogaerts, Hugues; Andre, Francis

    2003-06-02

    The widespread use of whole-cell pertussis vaccines in the second half of the 20th century have reduced the incidence of the disease significantly. However, in some countries, concerns about the reactogenicity and potential neurological damage associated with whole-cell vaccines led to a decrease in vaccine acceptance and an increase in morbidity and mortality of pertussis in several countries. This prompted the development of less reactogenic acellular pertussis vaccines combined with diphtheria and tetanus toxoids, initially in Japan and later in other countries. In Europe, the improved diphtheria, tetanus and acellular pertussis (DTPa) vaccine was first introduced in March 1994. The pertussis component of this DTPa vaccine, developed by Glaxo SmithKline, consists of pertussis toxoid, filamentous haemagglutinin and pertactin. The vaccine is well tolerated, with a lower incidence of adverse reactions than after administration of whole-cell vaccines. The long-lasting efficacy and effectiveness of DTPa vaccines have been extensively documented and these are now the cornerstone of a large range of combined vaccines including DTPa-hepatitis B (HBV), DTPa-inactivated polio (IPV) and DTPa-HBV-IPV. A lyophilised Haemophilus influenzae type b (Hib) vaccine can be reconstituted with all of these liquid combinations. The introduction of well-tolerated and efficacious DTPa vaccines and their more polyvalent combinations has improved the acceptance and simplified the implementation of childhood immunisation. This paper is a review of the technical and scientific difficulties encountered and the lessons learned over the 10-year period that it took to develop and introduce six multivalent vaccines using the Glaxo SmithKline DTPa as a building block.

  16. Current state and challenges in developing oral vaccines.

    PubMed

    Vela Ramirez, Julia E; Sharpe, Lindsey A; Peppas, Nicholas A

    2017-05-15

    While vaccination remains the most cost effective strategy for disease prevention, communicable diseases persist as the second leading cause of death worldwide. There is a need to design safe, novel vaccine delivery methods to protect against unaddressed and emerging diseases. Development of vaccines administered orally is preferable to traditional injection-based formulations for numerous reasons including improved safety and compliance, and easier manufacturing and administration. Additionally, the oral route enables stimulation of humoral and cellular immune responses at both systemic and mucosal sites to establish broader and long-lasting protection. However, oral delivery is challenging, requiring formulations to overcome the harsh gastrointestinal (GI) environment and avoid tolerance induction to achieve effective protection. Here we address the rationale for oral vaccines, including key biological and physicochemical considerations for next-generation oral vaccine design. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Evaluating a strategy to deliver vaccine to white-tailed deer at a landscape level

    USGS Publications Warehouse

    Fischer, Justin W.; Blass, Chad R.; Walter, W. David; Anderson, Charles W.; Lavelle, Michael J.; Hall, Wayne H.; VerCauterren, Kurt C.

    2016-01-01

    Effective delivery of vaccines and other pharmaceuticals to wildlife populations is needed when zoonotic diseases pose a risk to public health and natural resources or have considerable economic consequences. The objective of our study was to develop a bait-distribution strategy for potential delivery of oral bovine tuberculosis (bTB) vaccine to white-tailed deer (Odocoileus virginianus) where deer are reservoirs for the disease. During 17 February and 2 March 2011, we created a grid of experimental bait stations (n = 64) on Sandhill Wildlife Management Area, Wisconsin, USA, to assess station densities needed to attract and deliver placebo baits to free-ranging white-tailed deer and look for associations among deer density, number of bait stations per deer, and bait consumption. We placed 1 L of commercially available alfalfa cubes at bait stations 652 m apart, and monitored stations with motion-activated cameras for 5 days to document visitation and consumption by deer and nontarget species. Deer discovered 38% of all bait stations within 37 hr, on average (SE = 3.91 hr), and consumed variable amounts of bait at each station. Deer were documented in 94% of all photographs of wildlife at bait stations. We found no correlation between bait consumption and deer density or the number of bait stations per deer. We provide the first information on use of baits by free-ranging deer and nontarget wildlife to eventually vaccinate deer against bTB at a landscape level. The results of this study can further the development of strategies in delivery of pharmaceuticals to free-ranging white-tailed deer.

  18. Management of MDR-TB in HIV co-infected patients in Eastern Europe: Results from the TB:HIV study.

    PubMed

    Efsen, A M W; Schultze, A; Miller, R F; Panteleev, A; Skrahin, A; Podlekareva, D N; Miro, J M; Girardi, E; Furrer, H; Losso, M H; Toibaro, J; Caylà, J A; Mocroft, A; Lundgren, J D; Post, F A; Kirk, O

    2018-01-01

    Mortality among HIV patients with tuberculosis (TB) remains high in Eastern Europe (EE), but details of TB and HIV management remain scarce. In this prospective study, we describe the TB treatment regimens of patients with multi-drug resistant (MDR) TB and use of antiretroviral therapy (ART). A total of 105 HIV-positive patients had MDR-TB (including 33 with extensive drug resistance) and 130 pan-susceptible TB. Adequate initial TB treatment was provided for 8% of patients with MDR-TB compared with 80% of those with pan-susceptible TB. By twelve months, an estimated 57.3% (95%CI 41.5-74.1) of MDR-TB patients had started adequate treatment. While 67% received ART, HIV-RNA suppression was demonstrated in only 23%. Our results show that internationally recommended MDR-TB treatment regimens were infrequently used and that ART use and viral suppression was well below the target of 90%, reflecting the challenging patient population and the environment in which health care is provided. Urgent improvement of management of patients with TB/HIV in EE, in particular for those with MDR-TB, is needed and includes widespread access to rapid TB diagnostics, better access to and use of second-line TB drugs, timely ART initiation with viral load monitoring, and integration of TB/HIV care. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  19. Virus like particles as a platform for cancer vaccine development.

    PubMed

    Ong, Hui Kian; Tan, Wen Siang; Ho, Kok Lian

    2017-01-01

    Cancers have killed millions of people in human history and are still posing a serious health problem worldwide. Therefore, there is an urgent need for developing preventive and therapeutic cancer vaccines. Among various cancer vaccine development platforms, virus-like particles (VLPs) offer several advantages. VLPs are multimeric nanostructures with morphology resembling that of native viruses and are mainly composed of surface structural proteins of viruses but are devoid of viral genetic materials rendering them neither infective nor replicative. In addition, they can be engineered to display multiple, highly ordered heterologous epitopes or peptides in order to optimize the antigenicity and immunogenicity of the displayed entities. Like native viruses, specific epitopes displayed on VLPs can be taken up, processed, and presented by antigen-presenting cells to elicit potent specific humoral and cell-mediated immune responses. Several studies also indicated that VLPs could overcome the immunosuppressive state of the tumor microenvironment and break self-tolerance to elicit strong cytotoxic lymphocyte activity, which is crucial for both virus clearance and destruction of cancerous cells. Collectively, these unique characteristics of VLPs make them optimal cancer vaccine candidates. This review discusses current progress in the development of VLP-based cancer vaccines and some potential drawbacks of VLPs in cancer vaccine development. Extracellular vesicles with close resembling to viral particles are also discussed and compared with VLPs as a platform in cancer vaccine developments.

  20. Phage display as a promising approach for vaccine development.

    PubMed

    Aghebati-Maleki, Leili; Bakhshinejad, Babak; Baradaran, Behzad; Motallebnezhad, Morteza; Aghebati-Maleki, Ali; Nickho, Hamid; Yousefi, Mehdi; Majidi, Jafar

    2016-09-29

    Bacteriophages are specific antagonists to bacterial hosts. These viral entities have attracted growing interest as optimal vaccine delivery vehicles. Phages are well-matched for vaccine design due to being highly stable under harsh environmental conditions, simple and inexpensive large scale production, and potent adjuvant capacities. Phage vaccines have efficient immunostimulatory effects and present a high safety profile because these viruses have made a constant relationship with the mammalian body during a long-standing evolutionary period. The birth of phage display technology has been a turning point in the development of phage-based vaccines. Phage display vaccines are made by expressing multiple copies of an antigen on the surface of immunogenic phage particles, thereby eliciting a powerful and effective immune response. Also, the ability to produce combinatorial peptide libraries with a highly diverse pool of randomized ligands has transformed phage display into a straightforward, versatile and high throughput screening methodology for the identification of potential vaccine candidates against different diseases in particular microbial infections. These libraries can be conveniently screened through an affinity selection-based strategy called biopanning against a wide variety of targets for the selection of mimotopes with high antigenicity and immunogenicity. Also, they can be panned against the antiserum of convalescent individuals to recognize novel peptidomimetics of pathogen-related epitopes. Phage display has represented enormous promise for finding new strategies of vaccine discovery and production and current breakthroughs promise a brilliant future for the development of different phage-based vaccine platforms.

  1. Dengue human infection models to advance dengue vaccine development.

    PubMed

    Larsen, Christian P; Whitehead, Stephen S; Durbin, Anna P

    2015-12-10

    Dengue viruses (DENV) currently infect approximately 400 million people each year causing millions to seek care and overwhelming the health care infrastructure in endemic areas. Vaccines to prevent dengue and therapeutics to treat dengue are not currently available. The efficacy of the most advanced candidate vaccine against symptomatic dengue in general and DENV-2 in particular was much lower than expected, despite the ability of the vaccine to induce neutralizing antibody against all four DENV serotypes. Because seroconversion to the DENV serotypes following vaccination was thought to be indicative of induced protection, these results have made it more difficult to assess which candidate vaccines should or should not be evaluated in large studies in endemic areas. A dengue human infection model (DHIM) could be extremely valuable to down-select candidate vaccines or therapeutics prior to engaging in efficacy trials in endemic areas. Two DHIM have been developed to assess the efficacy of live attenuated tetravalent (LATV) dengue vaccines. The first model, developed by the Laboratory of Infectious Diseases at the U. S. National Institutes of Health, utilizes a modified DENV-2 strain DEN2Δ30. This virus was derived from the DENV-2 Tonga/74 that caused only very mild clinical infection during the outbreak from which it was recovered. DEN2Δ30 induced viremia in 100%, rash in 80%, and neutropenia in 27% of the 30 subjects to whom it was given. The Walter Reed Army Institute of Research (WRAIR) is developing a DHIM the goal of which is to identify DENV that cause symptomatic dengue fever. WRAIR has evaluated seven viruses and has identified two that meet dengue fever criteria. Both of these models may be very useful in the evaluation and down-selection of candidate dengue vaccines and therapeutics. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Current Status of Syphilis Vaccine Development: Need, Challenges, Prospects

    PubMed Central

    Cameron, Caroline E.; Lukehart, Sheila A.

    2013-01-01

    Syphilis is a multistage disease caused by the invasive spirochete Treponema pallidum subsp. pallidum. Despite inexpensive and effective antibiotic therapy, syphilis remains a prevalent disease in developing countries and has re-emerged as a public health threat in developed nations. In addition to the medical burden imparted by infectious syphilis, congenital syphilis is considered the most significant infectious disease affecting fetuses and newborns worldwide, and individuals afflicted with syphilis have an enhanced risk for HIV transmission and acquisition. The global disease burden of syphilis and failure of decades of public health efforts to stem the incidence of disease highlight the need for an effective syphilis vaccine. Although challenges associated with T. pallidum research have impeded understanding of this pathogen, the existence of a relevant animal model has enabled insight into the correlates of disease protection. Complete protection against infection has been achieved in the animal model using an extended immunization regimen of γ-irradiated T. pallidum, demonstrating the importance of treponemal surface components in generation of protective immunity and the feasibility of syphilis vaccine development. Syphilis is a prime candidate for development of a successful vaccine due to the (1) research community’s accumulated knowledge of immune correlates of protection; (2) existence of a relevant animal model that enables effective pre-clinical analyses; (3) universal penicillin susceptibility of T. pallidum which enhances the attractiveness of clinical vaccine trials; and (4) significant public health benefit a vaccine would have on reduction of infectious/congenital syphilis and HIV rates. Critical personnel, research and market gaps need to be addressed before the goal of a syphilis vaccine can be realized, including recruitment of additional researchers to the T. pallidum research field with a proportional increase in research funding

  3. A multi-antigenic MVA vaccine increases efficacy of combination chemotherapy against Mycobacterium tuberculosis.

    PubMed

    Leung-Theung-Long, Stéphane; Coupet, Charles-Antoine; Gouanvic, Marie; Schmitt, Doris; Ray, Aurélie; Hoffmann, Chantal; Schultz, Huguette; Tyagi, Sandeep; Soni, Heena; Converse, Paul J; Arias, Lilibeth; Kleinpeter, Patricia; Sansas, Benoît; Mdluli, Khisimuzi; Vilaplana, Cristina; Cardona, Pere-Joan; Nuermberger, Eric; Marchand, Jean-Baptiste; Silvestre, Nathalie; Inchauspé, Geneviève

    2018-01-01

    Despite the existence of the prophylactic Bacille Calmette-Guérin (BCG) vaccine, infection by Mycobacterium tuberculosis (Mtb) remains a major public health issue causing up to 1.8 million annual deaths worldwide. Increasing prevalence of Mtb strains resistant to antibiotics represents an urgent threat for global health that has prompted a search for alternative treatment regimens not subject to development of resistance. Immunotherapy constitutes a promising approach to improving current antibiotic treatments through engagement of the host's immune system. We designed a multi-antigenic and multiphasic vaccine, based on the Modified Vaccinia Ankara (MVA) virus, denoted MVATG18598, which expresses ten antigens classically described as representative of each of different phases of Mtb infection. In vitro analysis coupled with multiple-passage evaluation demonstrated that this vaccine is genetically stable, i.e. fit for manufacturing. Using different mouse strains, we show that MVATG18598 vaccination results in both Th1-associated T-cell responses and cytolytic activity, targeting all 10 vaccine-expressed Mtb antigens. In chronic post-exposure mouse models, MVATG18598 vaccination in combination with an antibiotic regimen decreases the bacterial burden in the lungs of infected mice, compared with chemotherapy alone, and is associated with long-lasting antigen-specific Th1-type T cell and antibody responses. In one model, co-treatment with MVATG18598 prevented relapse of the disease after treatment completion, an important clinical goal. Overall, results demonstrate the capacity of the therapeutic MVATG18598 vaccine to improve efficacy of chemotherapy against TB. These data support further development of this novel immunotherapeutic in the treatment of Mtb infections.

  4. Latent TB infection and pulmonary TB disease among patients with diabetes mellitus in Bandung, Indonesia.

    PubMed

    Koesoemadinata, Raspati C; McAllister, Susan M; Soetedjo, Nanny N M; Febni Ratnaningsih, Dwi; Ruslami, Rovina; Kerry, Sarah; Verrall, Ayesha J; Apriani, Lika; van Crevel, Reinout; Alisjahbana, Bachti; Hill, Philip C

    2017-02-01

    Screening and treatment of latent TB infection (LTBI) and TB disease could reduce diabetes mellitus (DM)-associated TB. We aimed to describe the prevalence of LTBI and pulmonary TB among patients with DM in a TB-endemic setting. Patients with DM attending a hospital and community centres in Bandung, Indonesia, underwent LTBI screening using interferon gamma release assay (IGRA). TB was investigated by sputum smear, culture and x-ray. TB contacts from a parallel study were age- and sex-matched to patients with DM to compare LTBI and TB disease prevalence. Of 682 patients with DM screened, 651 (95.5%) were eligible. Among 'TB disease-free' patients, LTBI prevalence was 38.9% (206/530; 95% CI 34.7-43.2). Patients with DM were less likely to be IGRA positive than TB contacts (38.6%, 54/140; 95% CI 30.5-46.6 vs 68.6%, 96/140; 95% CI 60.9-72.3: p<0.001); but had a higher disease prevalence (4.9%, 8/164; 95% CI 1.6-8.2 vs 1.2%, 2/164; 95% CI -0.5 to 2.9: p=0.054). Patients with DM in crowded households had increased risk of LTBI (AOR 1.71; 95% CI 1.19-2.45). LTBI prevalence in patients with DM was lower than in household contacts, but patients with DM were more likely to have TB disease. Further studies should explore possible benefits of LTBI screening and preventive therapy in patients with DM in TB-endemic settings. © The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Malaria vaccine research and development: the role of the WHO MALVAC committee

    PubMed Central

    2013-01-01

    The WHO Malaria Vaccine Advisory Committee (MALVAC) provides advice to WHO on strategic priorities, activities and technical issues related to global efforts to develop vaccines against malaria. MALVAC convened a series of meetings to obtain expert, impartial consensus views on the priorities and best practice for vaccine-related research and development strategies. The technical areas covered during these consultations included: guidance on clinical trial design for candidate sporozoite and asexual blood stage vaccines; measures of efficacy of malaria vaccines in Phase IIb and Phase III trials; standardization of immunoassays; the challenges of developing assays and designing trials for interventions against malaria transmission; modelling impact of anti-malarial interventions; whole organism malaria vaccines, and Plasmodium vivax vaccine-related research and evaluation. These informed discussions and opinions are summarized here to provide guidance on harmonization of strategies to help ensure high standards of practice and comparability between centres and the outcome of vaccine trials. PMID:24112689

  6. Thermally stimulated properties in ZnSe:Tb and ZnSe:(Mn, Tb) phosphors

    NASA Astrophysics Data System (ADS)

    Mishra, A. K.; Mishra, S. K.; Pandey, S. P.; Lakshmi Mishra, Kshama

    2018-02-01

    Thermoluminescence studies were performed of ZnSe:Tb and ZnSe:(Mn, Tb) phosphors. A method of preparation for ZnSe phosphors doped with Tb and (Mn, Tb) has been discussed. The thermoluminescence (TL) properties of these phosphors have been studied from 100 to 370 K temperature after exciting by UV radiation (365 nm) at three uniform heating rates 0.4, 0.6 and 0.9 K/s. The trapping parameters like trap depth, lifetime of electrons and capture cross-section have also been determined using various methods.

  7. Effectiveness of TB sensitization initiatives in improving the involvement of self help group members in rural TB control in south India.

    PubMed

    Thomas, Beena; Priscilla Rebecca, B; Dhanalakshmi, A; Rani, S; Deepa Lakshmi, A; Watson, Basilea; Vijayalakshmi, R; Muniyandi, M; Karikalan, N

    2016-12-01

    The 'End TB strategy' has highlighted the importance of inter-sectoral collaboration and community mobilization for achieving zero TB deaths by 2020. The aim of the study was to develop and test a model TB sensitization programme involving self help groups (SHGs). This experimental study was conducted in two blocks (intervention and control), in Tiruvallur district. The intervention content included short-lecture, musical story telling activity, role play, short film on TB. The impact was compared at baseline, third and sixth months in terms of SHGs' awareness, promotion of awareness, identification and referral of presumptive TB cases and provision of TB treatment. A total of 764 vs 796 SHGs were enrolled in control and intervention groups, respectively. The knowledge attitude, and practice score (lower score indicated a better attitude and practice), from baseline to 6 months was significantly reduced (29 to 24) in the intervention group. Similarly, a significant difference was observed in identification and referral of chest symptomatics in the intervention group at 3 and 6 months. During the 3 month follow-up a significantly higher proportion of SHG members were involved in TB awareness activities in the intervention (623/748 [83.3%]) vs control group (471/728 [64.7%]; p<0.001). Findings from this study highlight the feasibility of involving SHGs through a model TB sensitization program for strengthening TB prevention and control activities. © The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Effect of glycemic control and type of diabetes treatment on unsuccessful TB treatment outcomes among people with TB-Diabetes: A systematic review

    PubMed Central

    Jeyashree, Kathiresan; Mahajan, Preetam; Shah, Amar N.; Kirubakaran, Richard; Rao, Raghuram; Kumar, Ajay M. V.

    2017-01-01

    Background Stringent glycemic control by using insulin as a replacement or in addition to oral hypoglycemic agents (OHAs) has been recommended for people with tuberculosis and diabetes mellitus (TB-DM). This systematic review (PROSPERO 2016:CRD42016039101) analyses whether this improves TB treatment outcomes. Objectives Among people with drug-susceptible TB and DM on anti-TB treatment, to determine the effect of i) glycemic control (stringent or less stringent) compared to poor glycemic control and ii) insulin (only or with OHAs) compared to ‘OHAs only’ on unsuccessful TB treatment outcome(s). We looked for unfavourable TB treatment outcomes at the end of intensive phase and/or end of TB treatment (minimum six months and maximum 12 months follow up). Secondary outcomes were development of MDR-TB during the course of treatment, recurrence after 6 months and/or after 1 year post successful treatment completion and development of adverse events related to glucose lowering treatment (including hypoglycemic episodes). Methods All interventional studies (with comparison arm) and cohort studies on people with TB-DM on anti-TB treatment reporting glycemic control, DM treatment details and TB treatment outcomes were eligible. We searched electronic databases (EMBASE, PubMed, Google Scholar) and grey literature between 1996 and April 2017. Screening, data extraction and risk of bias assessment were done independently by two investigators and recourse to a third investigator, for resolution of differences. Results After removal of duplicates from 2326 identified articles, 2054 underwent title and abstract screening. Following full text screening of 56 articles, nine cohort studies were included. Considering high methodological and clinical heterogeneity, we decided to report the results qualitatively and not perform a meta-analysis. Eight studies dealt with glycemic control, of which only two were free of the risk of bias (with confounder-adjusted measures of effect). An

  9. Effect of glycemic control and type of diabetes treatment on unsuccessful TB treatment outcomes among people with TB-Diabetes: A systematic review.

    PubMed

    Shewade, Hemant Deepak; Jeyashree, Kathiresan; Mahajan, Preetam; Shah, Amar N; Kirubakaran, Richard; Rao, Raghuram; Kumar, Ajay M V

    2017-01-01

    Stringent glycemic control by using insulin as a replacement or in addition to oral hypoglycemic agents (OHAs) has been recommended for people with tuberculosis and diabetes mellitus (TB-DM). This systematic review (PROSPERO 2016:CRD42016039101) analyses whether this improves TB treatment outcomes. Among people with drug-susceptible TB and DM on anti-TB treatment, to determine the effect of i) glycemic control (stringent or less stringent) compared to poor glycemic control and ii) insulin (only or with OHAs) compared to 'OHAs only' on unsuccessful TB treatment outcome(s). We looked for unfavourable TB treatment outcomes at the end of intensive phase and/or end of TB treatment (minimum six months and maximum 12 months follow up). Secondary outcomes were development of MDR-TB during the course of treatment, recurrence after 6 months and/or after 1 year post successful treatment completion and development of adverse events related to glucose lowering treatment (including hypoglycemic episodes). All interventional studies (with comparison arm) and cohort studies on people with TB-DM on anti-TB treatment reporting glycemic control, DM treatment details and TB treatment outcomes were eligible. We searched electronic databases (EMBASE, PubMed, Google Scholar) and grey literature between 1996 and April 2017. Screening, data extraction and risk of bias assessment were done independently by two investigators and recourse to a third investigator, for resolution of differences. After removal of duplicates from 2326 identified articles, 2054 underwent title and abstract screening. Following full text screening of 56 articles, nine cohort studies were included. Considering high methodological and clinical heterogeneity, we decided to report the results qualitatively and not perform a meta-analysis. Eight studies dealt with glycemic control, of which only two were free of the risk of bias (with confounder-adjusted measures of effect). An Indian study reported 30% fewer

  10. Considerations for sustainable influenza vaccine production in developing countries.

    PubMed

    Nannei, Claudia; Chadwick, Christopher; Fatima, Hiba; Goldin, Shoshanna; Grubo, Myriam; Ganim, Alexandra

    2016-10-26

    Through its Global Action Plan for Influenza Vaccines (GAP), the World Health Organization (WHO) in collaboration with the United States Department of Health and Human Services has produced a checklist to support policy-makers and influenza vaccine manufacturers in identifying key technological, political, financial, and logistical issues affecting the sustainability of influenza vaccine production. This checklist highlights actions in five key areas that are beneficial for establishing successful local vaccine manufacturing. These five areas comprise: (1) the policy environment and health-care systems; (2) surveillance systems and influenza evidence; (3) product development and manufacturing; (4) product approval and regulation; and (5) communication to support influenza vaccination. Incorporating the checklist into national vaccine production programmes has identified the policy gaps and next steps for countries involved in GAP's Technology Transfer Initiative. Lessons learnt from country experiences provide context and insight that complement the checklist's goal of simplifying the complexities of influenza prevention, preparedness, and vaccine manufacturing. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. The impact of globalization on vaccine development and availability.

    PubMed

    Milstien, Julie B; Kaddar, Miloud; Kieny, Marie Paule

    2006-01-01

    Globalization is likely to affect many aspects of public health, one of which is vaccine-preventable communicable diseases. Important forces include increased funding initiatives supporting immunization at the global level; regulatory harmonization; widespread intellectual property rights provisions through the World Trade Organization agreements; the emergence of developing-country manufacturers as major players in vaccine supply; and the appearance of new communicable disease threats, including those potentially linked to bioterrorism. All of these forces can affect, either positively and negatively, the development and availability of vaccines. Harnessing these will be a challenge for policymakers and immunization stakeholders.

  12. Vaccine development and deployment: opportunities and challenges in India.

    PubMed

    Gupta, Sanjukta Sen; Nair, G Balakrish; Arora, Narendra Kumar; Ganguly, Nirmal Kumar

    2013-04-18

    The Indian economy is among the fastest growing economies in the world. The country forayed into manufacturing vaccines starting with a few public-sector manufacturers in the late 1960s but has emerged as the major supplier of basic Expanded Programme on Immunization vaccines to the United Nations Children's Fund (UNICEF) because of substantial private-sector investment in the area. The Indian vaccine industry is now able to produce new and more complex vaccines such as the meningitis, Haemophilus influenzae type b, and pneumococcal conjugate vaccines, rotavirus vaccine and influenza A (H1N1) vaccines. This has been possible because of an attractive investment environment, effective and innovative governmental support, international partnerships and the growing in-country technical work force. A large number of vaccines, including those mentioned, is available and administered in the private sector within the country, but India has been slow in introducing new vaccines in its publically funded programs. Growth in the economy and technological accomplishments are not reflected in a reduction in health inequalities, and India continues to contribute significantly to global child mortality figures. This paper reviews the development of the Indian vaccine industry, policy support for it and its current status. It also highlights opportunities and challenges for the introduction of new and underutilized vaccines at home. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Progress in the development of photodynamic-therapy-generated cancer vaccines

    NASA Astrophysics Data System (ADS)

    Korbelik, Mladen; Sun, Jinghai

    2003-07-01

    Upon giving an outline on vaccines in general, their history and priorities for future development, this paper gives a brief summary of the advances in the generation of cancer vaccines from the first attempts made over 100 years ago to those currently evaluted in clinical trials. This is followed by discussing hte intitial achievements in the investigation of cancer vaccines generated by photodynamic therapy (PDT). Recent contributions from our research to the understanding of how PDT-generated cancer vaccines work and their advantages compared to other types of cancer vaccines are discussed.

  14. Accelerating vaccine development and deployment: report of a Royal Society satellite meeting

    PubMed Central

    Bregu, Migena; Draper, Simon J.; Hill, Adrian V. S.; Greenwood, Brian M.

    2011-01-01

    The Royal Society convened a meeting on the 17th and 18th November 2010 to review the current ways in which vaccines are developed and deployed, and to make recommendations as to how each of these processes might be accelerated. The meeting brought together academics, industry representatives, research sponsors, regulators, government advisors and representatives of international public health agencies from a broad geographical background. Discussions were held under Chatham House rules. High-throughput screening of new vaccine antigens and candidates was seen as a driving force for vaccine discovery. Multi-stakeholder, small-scale manufacturing facilities capable of rapid production of clinical grade vaccines are currently too few and need to be expanded. In both the human and veterinary areas, there is a need for tiered regulatory standards, differentially tailored for experimental and commercial vaccines, to allow accelerated vaccine efficacy testing. Improved cross-fertilization of knowledge between industry and academia, and between human and veterinary vaccine developers, could lead to more rapid application of promising approaches and technologies to new product development. Identification of best-practices and development of checklists for product development plans and implementation programmes were seen as low-cost opportunities to shorten the timeline for vaccine progression from the laboratory bench to the people who need it. PMID:21893549

  15. [Infection prevention in newborns through maternal vaccination: current insights and developments].

    PubMed

    van der Maas, N A T; van Aerde, K; Bont, L J; Bekker, M N; Rots, N; de Melker, H E

    2016-01-01

    - In the first few months of life, newborns are vulnerable to infections.- Vaccination of the pregnant mother leads to transplacental antibody transfer, resulting in the best possible protection of the newborn.- Maternal vaccination has long been given for the prevention of tetanus in developing countries, and for the prevention of pertussis and influenza in developed countries, such as the United States, England and Belgium. These vaccinations give newborns good protection and, to date, no adverse effects are known for the foetus or the pregnancy.- Currently, phase 3 trials during pregnancy are ongoing following maternal vaccination against group B streptococci and respiratory syncytial virus. Here, again, no risks to mother or child have been reported.- Recently, the Dutch Health Council advised that all pregnant women in the Netherlands be vaccinated against pertussis in a vaccination programme.- This paper gives an overview of effectiveness, safety and practicalities of maternal vaccination.

  16. Diagnosing TB infection in children: analysis of discordances using in vitro tests and the tuberculin skin test.

    PubMed

    Altet-Gómez, N; De Souza-Galvao, M; Latorre, I; Milà, C; Jiménez, M A; Solsona, J; Cantos, A; Zamora, J J; Ruiz-Manzano, J; Ausina, V; Domínguez, J

    2011-05-01

    The aim of the present study was to compare the performance of the interferon (IFN)-γ tests (QuantiFERON®-TB Gold In-Tube (QFT-G-IT) and T-SPOT®.TB) with the tuberculin skin test (TST) in diagnosing tuberculosis (TB) infection in children, and to analyse discordant results. This was a prospective study including 98 children from contact-tracing studies and 68 children with TST indurations ≥ 5 mm recruited during public health screenings. Positive IFN-γ tests results were associated with risk of exposure (p<0.0001). T-SPOT.TB was positive in 11 (78.6%) out of 14 cases with active TB and QFT-G-IT in nine (64.3%) out of 14 cases. Sensitised T-cells against Mycobacterium avium were detected in six out of 12 children not vaccinated with bacille Calmette-Guérin (BCG), a TST induration 5-9 mm in diameter and both IFN-γ tests negative. In concordant IFN-γ tests results, a positive correlation was found (p = 0.0001) between the number of responding cells and the amount of IFN-γ released. However, in discordant IFN-γ tests results this correlation was negative (p = 0.371): an increase in the number of spot-forming cells correlated with a decrease in the amount of IFN-γ released. The use of IFN-γ tests is helpful for the diagnosis of TB infection, avoiding cross-reactions with BCG immunisation and nontuberculous mycobacterial infections. The analysis of highly discordant results requires further investigation to elucidate possible clinical implications.

  17. Approaches and Perspectives for Development of African Swine Fever Virus Vaccines

    PubMed Central

    Arias, Marisa; de la Torre, Ana; Dixon, Linda; Gallardo, Carmina; Laddomada, Alberto; Martins, Carlos; Parkhouse, R. Michael; Revilla, Yolanda; Rodriguez, Fernando; Sanchez-Vizcaino, Jose-Manuel

    2017-01-01

    African swine fever (ASF) is a complex disease of swine, caused by a large DNA virus belonging to the family Asfarviridae. The disease shows variable clinical signs, with high case fatality rates, up to 100%, in the acute forms. ASF is currently present in Africa and Europe where it circulates in different scenarios causing a high socio-economic impact. In most affected regions, control has not been effective in part due to lack of a vaccine. The availability of an effective and safe ASFV vaccines would support and enforce control–eradication strategies. Therefore, work leading to the rational development of protective ASF vaccines is a high priority. Several factors have hindered vaccine development, including the complexity of the ASF virus particle and the large number of proteins encoded by its genome. Many of these virus proteins inhibit the host’s immune system thus facilitating virus replication and persistence. We review previous work aimed at understanding ASFV–host interactions, including mechanisms of protective immunity, and approaches for vaccine development. These include live attenuated vaccines, and “subunit” vaccines, based on DNA, proteins, or virus vectors. In the shorter to medium term, live attenuated vaccines are the most promising and best positioned candidates. Gaps and future research directions are evaluated. PMID:28991171

  18. The development and manufacture of influenza vaccines

    PubMed Central

    Buckland, Barry C

    2015-01-01

    The development and manufacture of an Influenza vaccine is unlike any other product in the Vaccine industry because of the need to change composition on a yearly basis. The poor efficacy of Influenza vaccines over the past 2 y in the Northern Hemisphere invites questions on how the vaccines are manufactured and how change in vaccine composition is controlled. The opinion expressed in this commentary is that the risk of not making the correct HA protein is increased by the need to adapt the new seasonal virus for good propagation in embryonated chicken eggs. This adaptation is required because not enough doses can be made in time for the new 'flu season unless productivity is reasonable. This problem is not necessarily solved by going to a cell culture host for virus propagation and that may explain why this more advanced technology approach is not more widely used. A vaccine based on hemagglutinin (HA) protein that does not involve Influenza virus propagation (such as Flublok®) side steps this particular problem. The exact HA sequence can be used as is in the virus. The technology can be run at large scale, already at 2 × 21,000L in Japan, in contrast to eggs where scale-up is by multiplication; the HA product is highly purified and made consistently in the form of rosettes. PMID:25844949

  19. Immunocontraception: Filamentous Bacteriophage as a Platform for Vaccine Development.

    PubMed

    Samoylova, Tatiana I; Braden, Timothy D; Spencer, Jennifer A; Bartol, Frank F

    2017-11-20

    Population control of domestic, wild, invasive, and captive animal species is a global issue of importance to public health, animal welfare and the economy. There is pressing need for effective, safe, and inexpensive contraceptive technologies to address this problem. Contraceptive vaccines, designed to stimulate the immune system in order to block critical reproductive events and suppress fertility, may provide a solution. Filamentous bacteriophages can be used as platforms for development of such vaccines. In this review authors highlight structural and immunogenic properties of filamentous phages, and discuss applications of phage-peptide vaccines for advancement of immunocontraception technology in animals. Phages can be engineered to display fusion (non-phage) peptides as coat proteins. Such modifications can be accomplished via genetic manipulation of phage DNA, or by chemical conjugation of synthetic peptides to phage surface proteins. Phage fusions with antigenic determinants induce humoral as well as cell-mediated immune responses in animals, making them attractive as vaccines. Additional advantages of the phage platform include environmental stability, low cost, and safety for immunized animals and those administering the vaccines. Filamentous phages are viable platforms for vaccine development that can be engineered with molecular and organismal specificity. Phage-based vaccines can be produced in abundance at low cost, are environmentally stable, and are immunogenic when administered via multiple routes. These features are essential for a contraceptive vaccine to be operationally practical in animal applications. Adaptability of the phage platform also makes it attractive for design of human immunocontraceptive agents. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  20. Immunocontraception: Filamentous Bacteriophage as a Platform for Vaccine Development

    PubMed Central

    Samoylova, Tatiana I.; Braden, Timothy D.; Spencer, Jennifer A.; Bartol, Frank F.

    2017-01-01

    Background: Population control of domestic, wild, invasive, and captive animal species is a global issue of importance to public health, animal welfare and the economy. There is pressing need for effective, safe, and inexpensive contraceptive technologies to ad-dress this problem. Contraceptive vaccines, designed to stimulate the immune system in order to block critical reproductive events and suppress fertility, may provide a solution. Fil-amentous bacteriophages can be used as platforms for development of such vaccines. Objective: In this review authors highlight structural and immunogenic properties of fila-mentous phages, and discuss applications of phage-peptide vaccines for advancement of immunocontraception technology in animals. Results: Phages can be engineered to display fusion (non-phage) peptides as coat proteins. Such modifications can be accomplished via genetic manipulation of phage DNA, or by chemical conjugation of synthetic peptides to phage surface proteins. Phage fusions with antigenic determinants induce humoral as well as cell-mediated immune responses in ani-mals, making them attractive as vaccines. Additional advantages of the phage platform include environmental stability, low cost, and safety for immunized animals and those ad-ministering the vaccines. Conclusion: Filamentous phages are viable platforms for vaccine development that can be engineered with molecular and organismal specificity. Phage-based vaccines can be pro-duced in abundance at low cost, are environmentally stable, and are immunogenic when administered via multiple routes. These features are essential for a contraceptive vaccine to be operationally practical in animal applications. Adaptability of the phage platform also makes it attractive for design of human immunocontraceptive agents. PMID:28901276

  1. Options for improving effectiveness of rotavirus vaccines in developing countries.

    PubMed

    Tissera, Marion S; Cowley, Daniel; Bogdanovic-Sakran, Nada; Hutton, Melanie L; Lyras, Dena; Kirkwood, Carl D; Buttery, Jim P

    2017-04-03

    Rotavirus gastroenteritis is a leading global cause of mortality and morbidity in young children due to diarrhea and dehydration. Over 85% of deaths occur in developing countries. In industrialised countries, 2 live oral rotavirus vaccines licensed in 2006 quickly demonstrated high effectiveness, dramatically reducing severe rotavirus gastroenteritis admissions in many settings by more than 90%. In contrast, the same vaccines reduced severe rotavirus gastroenteritis by only 30-60% in developing countries, but have been proven life-saving. Bridging this "efficacy gap" offers the possibility to save many more lives of children under the age of 5. The reduced efficacy of rotavirus vaccines in developing settings may be related to differences in transmission dynamics, as well as host luminal, mucosal and immune factors. This review will examine strategies currently under study to target the issue of reduced efficacy and effectiveness of oral rotavirus vaccines in developing settings.

  2. Options for improving effectiveness of rotavirus vaccines in developing countries

    PubMed Central

    Cowley, Daniel; Bogdanovic-Sakran, Nada; Hutton, Melanie L.; Lyras, Dena; Kirkwood, Carl D.; Buttery, Jim P.

    2017-01-01

    ABSTRACT Rotavirus gastroenteritis is a leading global cause of mortality and morbidity in young children due to diarrhea and dehydration. Over 85% of deaths occur in developing countries. In industrialised countries, 2 live oral rotavirus vaccines licensed in 2006 quickly demonstrated high effectiveness, dramatically reducing severe rotavirus gastroenteritis admissions in many settings by more than 90%. In contrast, the same vaccines reduced severe rotavirus gastroenteritis by only 30–60% in developing countries, but have been proven life-saving. Bridging this “efficacy gap” offers the possibility to save many more lives of children under the age of 5. The reduced efficacy of rotavirus vaccines in developing settings may be related to differences in transmission dynamics, as well as host luminal, mucosal and immune factors. This review will examine strategies currently under study to target the issue of reduced efficacy and effectiveness of oral rotavirus vaccines in developing settings. PMID:27835052

  3. Current State in the Development of Candidate Therapeutic HPV Vaccines

    PubMed Central

    Yang, Andrew; Jeang, Jessica; Cheng, Kevin; Cheng, Ting; Yang, Benjamin; Wu, T.-C.; Hung, Chien-Fu

    2016-01-01

    Summary The identification of human papillomavirus (HPV) as an etiological factor for HPV-associated malignancies creates the opportunity to control these cancers through vaccination. Currently, available preventive HPV vaccines have not yet demonstrated strong evidences for therapeutic effects against established HPV infections and lesions. Furthermore, HPV infections remain extremely common. Thus, there is urgent need for therapeutic vaccines to treat existing HPV infections and HPV-associated diseases. Therapeutic vaccines differ from preventive vaccines in that they are aimed at generating cell-mediated immunity rather than neutralizing antibodies. The HPV-encoded early proteins, especially oncoproteins E6 and E7, form ideal targets for therapeutic HPV vaccines since they are consistently expressed in HPV-associated malignancies and precancerous lesions, playing crucial roles in the generation and maintenance of HPV-associated disease. Our review will cover various therapeutic vaccines in development for the treatment of HPV-associated lesions and cancers. Furthermore, we review strategies to enhance vaccine efficacy and the latest clinical trials on therapeutic HPV vaccines. PMID:26901118

  4. Beyond empiricism: Informing vaccine development through innate immunity research

    PubMed Central

    Levitz, Stuart M.; Golenbock, Douglas T.

    2012-01-01

    Summary While a great public heath success, vaccines provide suboptimal protection in some patient populations and are not available to protect against many infectious diseases. Insights from innate immunity research have led to a better understanding of how existing vaccines work and informed vaccine development. New adjuvants and delivery systems are being designed based upon their capacity to stimulate innate immune sensors and target antigens to dendritic cells, the cells responsible for initiating adaptive immune responses. Incorporating these adjuvants and delivery systems in vaccines can beneficially alter the quantitative and qualitative nature of the adaptive immune response resulting in enhanced protection. PMID:22424235

  5. [Introduction of vaccination against human papillomavirus in developing countries: update and perspectives].

    PubMed

    Hessel, L

    2009-08-01

    Cervical cancer and other diseases related to human papillomavirus (HPV) represent a global public health problem. Safe and effective vaccines are now available and already used in many industrialized countries. Immunization offers the best hope for protecting the population against a disease that is the second most deadly cancer in the developing world and the first most deadly in Africa. The World Health Organization currently recommends introduction of HVP vaccination in developing countries. Widespread vaccination could be beneficial in numerous domains other than primary prevention of cervical cancer. Efforts to overcome the numerous obstacles and speed up implementation of HVP vaccination programs are now underway in many areas ranging from related scientific issues such as epidemiology and clinical research to administrative concerns such as healthcare economics, vaccination guidelines, public acceptation, program funding, and universal access. Vaccine manufacturers have committed themselves to working in partnership with national and international organizations to ensure access to HPV vaccine for all countries regardless of economic level, Although numerous issues must be resolved to optimize the use of HPV vaccines and ensure synergistic integration of vaccination, screening and treatment, current initiatives and efforts should allow introduction of HPV vaccination in developing countries in a not too distant future.

  6. Comparison of the immunogenicity and protection against bovine tuberculosis following immunization by BCG-priming and boosting with adenovirus or protein based vaccines.

    PubMed

    Dean, G; Whelan, A; Clifford, D; Salguero, F J; Xing, Z; Gilbert, S; McShane, H; Hewinson, R G; Vordermeier, M; Villarreal-Ramos, B

    2014-03-05

    There is a requirement for vaccines or vaccination strategies that confer better protection against TB than the current live attenuated Mycobacterium bovis Bacillus Calmette-Guerin (BCG) vaccine for use in cattle. Boosting with recombinant viral vectors expressing mycobacterial proteins, such as Ag85A, has shown a degree of promise as a strategy for improving on the protection afforded by BCG. Experiments in small animal models have indicated that broadening the immune response to include mycobacterial antigens other than Ag85A, such as Rv0288, induced by boosting with Ad5 constructs has a direct effect on the protection afforded against TB. Here, we compared the immunogenicity and protection against challenge with M. bovis afforded by boosting BCG-vaccinated cattle with a human type 5 (Ad5)-based vaccine expressing the mycobacterial antigens Ag85A (Ad5-85A); or Ag85A, Rv0251, Rv0287 and Rv0288 (Ad5-TBF); or with protein TBF emulsified in adjuvant (Adj-TBF). Boosting with TBF broaden the immune response. The kinetics of Ad5-TBF and Adj-TBF were shown to be different, with effector T cell responses from the latter developing more slowly but being more durable than those induced by Ad5-TBF. No increase in protection compared to BCG alone was afforded by Ad5-TBF or Adj-TBF by gross pathology or bacteriology. Using histopathology, as a novel parameter of protection, we show that boosting BCG vaccinated cattle with Ad5-85A induced significantly better protection than BCG alone. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  7. Recent developments in Helicobacter pylori vaccination.

    PubMed

    Kusters, J G

    2001-01-01

    This reviews discusses the recent progress in the development of a vaccine against Helicobacter pylori. To date, this gram-negative, spiral-shaped bacterium is one of the most common infections of mankind. Infection usually occurs during childhood, and when left untreated results in lifelong colonization of the stomach. Helicobacter pylori infection is a chronic gastritis that can lead to peptic ulcer disease, gastric adenocarcinoma and gastric B-cell lymphoma. Antimicrobial therapy is currently the method of choice for curing H. pylori infection, but complex dosing, inconsistent efficiency, development of antibiotic resistance, costs and various side effects compromise widespread use. As a consequence, new strategies for the prevention and eradication of H. pylori infections are being explored. Vaccines are an attractive option, because they are both effective and economic in use. Natural infection with H. pylori usually results in a strong inflammatory Th1-type CD4(+)T-cell response that does not seem to have any protective effects. Successful vaccination studies indicate that a Th2-type response is required for protection, but the exact mechanisms involved in protective immunization are still poorly understood. Although commercial development of products for clinical trial is underway, many important issues, such as lack of a suitable mucosal adjuvant, and prevention of potential side effects, such as postimmunization gastritis, need to be resolved.

  8. Possibilities and challenges for developing a successful vaccine for leishmaniasis.

    PubMed

    Srivastava, Saumya; Shankar, Prem; Mishra, Jyotsna; Singh, Sarman

    2016-05-12

    Leishmaniasis is a vector-borne disease caused by different species of protozoan parasites of the genus Leishmania. It is a major health problem yet neglected tropical diseases, with approximately 350 million people worldwide at risk and more than 1.5 million infections occurring each year. Leishmaniasis has different clinical manifestations, including visceral (VL or kala-azar), cutaneous (CL), mucocutaneous (MCL), diffuse cutaneous (DCL) and post kala-azar dermal leishmaniasis (PKDL). Currently, the only mean to treat and control leishmaniasis is by rational medications and vector control. However, the number of available drugs is limited and even these are either exorbitantly priced, have toxic side effects or prove ineffective due to the emergence of resistant strains. On the other hand, the vector control methods are not so efficient. Therefore, there is an urgent need for developing a safe, effective, and affordable vaccine for the prevention of leishmaniasis. Although in recent years a large body of researchers has concentrated their efforts on this issue, yet only three vaccine candidates have gone for clinical trial, until date. These are: (i) killed vaccine in Brazil for human immunotherapy; (ii) live attenuated vaccine for humans in Uzbekistan; and (iii) second-generation vaccine for dog prophylaxis in Brazil. Nevertheless, there are at least half a dozen vaccine candidates in the pipeline. One can expect that, in the near future, the understanding of the whole genome of Leishmania spp. will expand the vaccine discovery and strategies that may provide novel vaccines. The present review focuses on the development and the status of various vaccines and potential vaccine candidates against leishmaniasis.

  9. Implementing the End TB Strategy in the Western Pacific Region: Translating vision into reality.

    PubMed

    Rahevar, Kalpeshsinh; Fujiwara, Paula I; Ahmadova, Shalala; Morishita, Fukushi; Reichman, Lee B

    2018-04-12

    The End TB Strategy aims to end the global tuberculosis (TB) epidemic by 2035 in line with the sustainable development goals targets and has been implemented in the World Health Organization (WHO) Western Pacific Region since 2015. Significant progress has been made in implementing this strategy. However, several challenges still remain. In 2016, an estimated 1.8 million people developed TB in the region, and of these about 20% were missed by national TB programmes. The gap in diagnosis and enrolment as well as treatment completion is greater with drug-resistant TB. Many TB-affected families face catastrophic costs due to the disease. Sustaining financing for TB care is a long-term challenge in many countries. This article emphasizes targeted interventions in high-risk populations, including systematic screening and patient-centred TB care. Several other approaches including improving TB diagnostic tools and algorithm, and engaging all care providers are suggested to find missing TB patients. Drug-resistant TB requires additional resourcing for laboratories, enrolment and patient support. Specific measures are required at different levels to mitigate financial burden due to TB including linking TB to overall social protection schemes. The Moscow Ministerial conference in 2017 and upcoming United Nations (UN) 2018 high-level meeting provide an opportunity to raise TB higher on the global agenda, forge partnerships and move towards universal health coverage. © 2018 Asian Pacific Society of Respirology.

  10. New developments and concepts related to biomarker application to vaccines

    PubMed Central

    Ahmed, S. Sohail; Black, Steve; Ulmer, Jeffrey

    2012-01-01

    Summary This minireview will provide a perspective on new developments and concepts related to biomarker applications for vaccines. In the context of preventive vaccines, biomarkers have the potential to predict adverse events in select subjects due to differences in genetic make‐up/underlying medical conditions or to predict effectiveness (good versus poor response). When expanding them to therapeutic vaccines, their utility in identification of patients most likely to respond favourably (or avoid potentially negative effects of treatment) becomes self‐explanatory. Despite the progress made so far on dissection of various pathways of biological significance in humans, there is still plenty to unravel about the mysteries related to the quantitative and qualitative aspects of the human host response. This review will provide a focused overview of new concepts and developments in the field of vaccine biomarkers including (i) vaccine‐dependent signatures predicting subject response and safety, (ii) predicting therapeutic vaccine efficacy in chronic diseases, (iii) exploring the genetic make‐up of the host that may modulate subject‐specific adverse events or affect the quality of immune responses, and (iv) the topic of volunteer stratification as a result of biomarker screening (e.g. for therapeutic vaccines but also potentially for preventive vaccines) or as a reflection of an effort to compare select groups (e.g. vaccinated subjects versus patients recovering from infection) to enable the discovery of clinically relevant biomarkers for preventive vaccines. PMID:21895991

  11. Immunity, immunopathology, and human vaccine development against sexually transmitted Chlamydia trachomatis

    PubMed Central

    Rey-Ladino, Jose; Ross, Allen GP; Cripps, Allan W

    2014-01-01

    This review examines the immunity, immunopathology, and contemporary problems of vaccine development against sexually transmitted Chlamydia trachomatis. Despite improved surveillance and treatment initiatives, the incidence of C. trachomatis infection has increased dramatically over the past 30 years in both the developed and developing world. Studies in animal models have shown that protective immunity to C. trachomatis is largely mediated by Th1 T cells producing IFN-γ which is needed to prevent dissemination of infection. Similar protection appears to develop in humans but in contrast to mice, immunity in humans may take years to develop. Animal studies and evidence from human infection indicate that immunity to C. trachomatis is accompanied by significant pathology in the upper genital tract. Although no credible evidence is currently available to indicate that autoimmunity plays a role, nevertheless, this underscores the necessity to design vaccines strictly based on chlamydial-specific antigens and to avoid those displaying even minimal sequence homologies with host molecules. Current advances in C. trachomatis vaccine development as well as alternatives for designing new vaccines for this disease are discussed. A novel approach for chlamydia vaccine development, based on targeting endogenous dendritic cells, is described. PMID:25483666

  12. Heterogeneity of Rotavirus Vaccine Efficacy Among Infants in Developing Countries.

    PubMed

    Gruber, Joann F; Hille, Darcy A; Liu, G Frank; Kaplan, Susan S; Nelson, Micki; Goveia, Michelle G; Mast, T Christopher

    2017-01-01

    Rotavirus is the leading cause of severe diarrhea worldwide in young children. Although rotavirus vaccine efficacy is high in developed countries, efficacy is lower in developing countries. Here, we investigated heterogeneity of rotavirus vaccine efficacy by infant characteristics in developing countries. An exploratory, post hoc analysis was conducted using randomized controlled trial data of the pentavalent rotavirus vaccine (RV5) conducted in Africa and Asia (NCT00362648). Infants received either 3 doses of vaccine/placebo and were followed for up to 2 years. Within subgroups, vaccine efficacies and 95% confidence intervals (CIs) against rotavirus gastroenteritis (RVGE) were estimated using Poisson regression. We assessed heterogeneity of efficacy by age at first dose, gender, breastfeeding status and nutrition status. African children receiving the first dose at <8 weeks had lower efficacy (23.7%; 95% CI: -8.2%-46.3%) than those vaccinated at ≥8 weeks (59.1%; 95% CI: 34.0%-74.6%). Marginally statistically significant differences were observed by age at first dose, gender and underweight status in Ghana and gender in Asian countries. Heterogeneity of efficacy was observed for age at first dose in African countries. This was an exploratory analysis; additional studies are needed to validate these results.

  13. Development of an epitope-based HIV-1 vaccine strategy from HIV-1 lipopeptide to dendritic-based vaccines.

    PubMed

    Surenaud, Mathieu; Lacabaratz, Christine; Zurawski, Gérard; Lévy, Yves; Lelièvre, Jean-Daniel

    2017-10-01

    Development of a safe, effective and globally affordable Human Immunodeficiency Virus strain 1 (HIV-1) vaccine offers the best hope for future control of the HIV-1 pandemic. However, with the exception of the recent RV144 trial, which elicited a modest level of protection against infection, no vaccine candidate has shown efficacy in preventing HIV-1 infection or in controlling virus replication in humans. There is also a great need for a successful immunotherapeutic vaccine since combination antiretroviral therapy (cART) does not eliminate the reservoir of HIV-infected cells. But to date, no vaccine candidate has proven to significantly alter the natural history of an individual with HIV-1 infection. Areas covered: For over 25 years, the ANRS (France Recherche Nord&Sud Sida-HIV hépatites) has been committed to an original program combining basic science and clinical research developing an epitope-based vaccine strategy to induce a multiepitopic cellular response against HIV-1. This review describes the evolution of concepts, based on strategies using HIV-1 lipopeptides towards the use of dendritic cell (DC) manipulation. Expert commentary: Understanding the crucial role of DCs in immune responses allowed moving from the non-specific administration of HIV-1 sequences with lipopeptides to DC-based vaccines. These DC-targeting strategies should improve HIV-1 vaccine efficacy.

  14. An update on vaccines for tuberculosis - there is more to it than just waning of BCG efficacy with time.

    PubMed

    Romano, Marta; Huygen, Kris

    2012-12-01

    Apart from better diagnostics and new anti-microbial drugs, an effective vaccine for tuberculosis is urgently needed to halt this poverty-related disease, afflicting millions of people worldwide. After a general introduction on the global threat of tuberculosis, the pros and cons of the existing M. bovis BCG vaccine are discussed. As the correlates of protection against tuberculosis remain largely unknown, new findings in biomarker research are described. Next, an update on the ongoing Phase I and Phase II clinical trials is given. Finally, some of the most promising novel pre-clinical developments using live attenuated vaccines, sub-unit vaccines, prime-boost strategies, and new vaccination routes are discussed. The field has made considerable progress and 12 vaccine candidates have now actually entered Phase I or Phase IIa and IIb clinical trials. It is argued that the variable protection conferred by the existing BCG vaccine against reactivation of latent TB is caused not only by waning of its efficacy with time but also by its weak induction of MHC class I restricted responses. Prime-boost strategies based on the actual BCG vaccine may not be sufficient to overcome this hurdle. The use of plasmid DNA vaccination might offer a solution.

  15. R&D in Vaccines Targeting Neglected Diseases: An Exploratory Case Study Considering Funding for Preventive Tuberculosis Vaccine Development from 2007 to 2014

    PubMed Central

    Costa Barbosa Bessa, Theolis; Santos de Aragão, Erika; Medeiros Guimarães, Jane Mary

    2017-01-01

    Based on an exploratory case study regarding the types of institutions funding the research and development to obtain new tuberculosis vaccines, this article intends to provoke discussion regarding the provision of new vaccines targeting neglected disease. Although our findings and discussion are mainly relevant to the case presented here, some aspects are more generally applicable, especially regarding the dynamics of development in vaccines to prevent neglected diseases. Taking into account the dynamics of innovation currently seen at work in the vaccine sector, a highly concentrated market dominated by few multinational pharmaceutical companies, we feel that global PDP models can play an important role throughout the vaccine development cycle. In addition, the authors call attention to issues surrounding the coordination of actors and resources in the research, development, manufacturing, and distribution processes of vaccine products arising from PDP involvement. PMID:28133608

  16. Pharmacoeconomic spotlight on rotavirus vaccine RIX4414 (Rotarix™) in developed countries.

    PubMed

    Plosker, Greg L

    2012-12-01

    The most common cause of severe diarrhea in infants and young children is rotavirus gastroenteritis (RVGE), which is associated with significant morbidity, healthcare resource use, and direct and indirect costs in industrialized nations. The monovalent rotavirus vaccine RIX4414 (Rotarix™) is administered as a two-dose oral series in infants and has demonstrated protective efficacy against RVGE in clinical trials conducted in developed countries. In addition, various naturalistic studies have demonstrated 'real-world' effectiveness after the introduction of widespread rotavirus vaccination programs in the community setting. Numerous cost-effectiveness analyses have been conducted in developed countries in which a universal rotavirus vaccination program using RIX4414 was compared with no universal rotavirus vaccination program. There was a high degree of variability in base-case results across studies even when the studies were conducted in the same country, often reflecting differences in the selection of data sources or assumptions used to populate the models. In addition, results were sensitive to plausible changes in a number of key input parameters. As such, it is not possible to definitively state whether a universal rotavirus vaccination program with RIX4414 is cost effective in developed countries, although results of some analyses in some countries suggest this is the case. In addition, international guidelines advocate universal vaccination of infants and children against rotavirus. It is also difficult to draw conclusions regarding the cost effectiveness of rotavirus vaccine RIX4414 relative to that of the pentavalent rotavirus vaccine, which is administered as a three-dose oral series. Although indirect comparisons in cost-effectiveness analyses indicate that RIX4414 provided more favorable incremental cost-effectiveness ratios when each vaccine was compared with no universal rotavirus vaccination program, results were generally sensitive to vaccine

  17. Antigen-Specific Interferon-Gamma Responses and Innate Cytokine Balance in TB-IRIS

    PubMed Central

    Goovaerts, Odin; Jennes, Wim; Massinga-Loembé, Marguerite; Ceulemans, Ann; Worodria, William; Mayanja-Kizza, Harriet; Colebunders, Robert; Kestens, Luc

    2014-01-01

    Background Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB patients receiving antiretroviral therapy (ART). TB-IRIS could be associated with an exaggerated immune response to TB-antigens. We compared the recovery of IFNγ responses to recall and TB-antigens and explored in vitro innate cytokine production in TB-IRIS patients. Methods In a prospective cohort study of HIV-TB co-infected patients treated for TB before ART initiation, we compared 18 patients who developed TB-IRIS with 18 non-IRIS controls matched for age, sex and CD4 count. We analyzed IFNγ ELISpot responses to CMV, influenza, TB and LPS before ART and during TB-IRIS. CMV and LPS stimulated ELISpot supernatants were subsequently evaluated for production of IL-12p70, IL-6, TNFα and IL-10 by Luminex. Results Before ART, all responses were similar between TB-IRIS patients and non-IRIS controls. During TB-IRIS, IFNγ responses to TB and influenza antigens were comparable between TB-IRIS patients and non-IRIS controls, but responses to CMV and LPS remained significantly lower in TB-IRIS patients. Production of innate cytokines was similar between TB-IRIS patients and non-IRIS controls. However, upon LPS stimulation, IL-6/IL-10 and TNFα/IL-10 ratios were increased in TB-IRIS patients compared to non-IRIS controls. Conclusion TB-IRIS patients did not display excessive IFNγ responses to TB-antigens. In contrast, the reconstitution of CMV and LPS responses was delayed in the TB-IRIS group. For LPS, this was linked with a pro-inflammatory shift in the innate cytokine balance. These data are in support of a prominent role of the innate immune system in TB-IRIS. PMID:25415590

  18. A systematic review and meta-analysis for the adverse effects, immunogenicity and efficacy of Lyme disease vaccines: Guiding novel vaccine development.

    PubMed

    Badawi, Alaa; Shering, Maria; Rahman, Shusmita; Lindsay, L Robbin

    2017-04-20

    Lyme borreliosis (LB) is the most prevalent arthropod-borne infectious disease in North America. Currently, no vaccine is available to prevent LB in humans, although monovalent and multivalent vaccines have been developed in the past. The aim of the current study is to conduct a systematic review and meta-analysis to evaluate and compare the findings from these two classes of vaccines for their reactogenicity, immunogenicity and efficacy, in the hope this may assist in the development of future vaccines. A search strategy was developed for online databases (PubMed, Ovid MEDLINE, and Embase). Search terms used were "vaccine/vaccination", "Lyme disease/Borreliosis", "clinical trial(s)" and "efficacy". Only seven clinical trials were included to compare the results of the monovalent vaccines to those of the multivalent one. Meta-analyses were conducted to evaluate the reactogenicity and immunogenicity of the two vaccine classes. Odds ratio (OR) for LB (and 95% confidence intervals; 95% CI) were calculated for the efficacy of the monovalent vaccine from three different clinical trials at different dose schedules. Incidence of redness (local adverse effect) and fever (systemic side effect) were, respectively, 6.8- and 2.9-fold significantly lower (p < 0.05) in individuals who received multivalent vaccines compared to those receiving the monovalent one. Incidences of all other local and systemic adverse effects were non-significantly lower in the multivalent vaccine compared to the monovalent vaccines. Seroprotection was comparable among individuals who received the two vaccine classes at the 30 μg dose level. Efficacy in the prevention of LB was only evaluated for the monovalent vaccines. OR of LB ranged from 0.49 (95% CI: 0.14-0.70; p < 0.005, vs. placebo) to 0.31 (95% CI: 0.26-0.63; p < 0.005) for the initial and final doses respectively, with an overall OR of 0.4 (95% CI: 0.26-0.63, p < 0.001). The current study further validates that the monovalent and

  19. 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.

  20. Live attenuated hepatitis A vaccines developed in China

    PubMed Central

    Xu, Zhi-Yi; Wang, Xuan-Yi

    2014-01-01

    Two live, attenuated hepatitis A vaccines, H2 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 H2 vaccine or of marmoset with LA-1 vaccine failed, and no evidence was found for person-to-person transmission of H2 strain or for marmoset-to-marmoset transmission of LA-1 strain by close contact. H2 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 (HA) 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 a county of China for 14 years following introduction of the H2 live vaccine into the Expanded Immunization Program (EPI) in 1992. PMID:24280971

  1. Current status of syphilis vaccine development: need, challenges, prospects.

    PubMed

    Cameron, Caroline E; Lukehart, Sheila A

    2014-03-20

    Syphilis is a multistage disease caused by the invasive spirochete Treponema pallidum subsp. pallidum. Despite inexpensive and effective antibiotic therapy, syphilis remains a prevalent disease in developing countries and has re-emerged as a public health threat in developed nations. In addition to the medical burden imparted by infectious syphilis, congenital syphilis is considered the most significant infectious disease affecting fetuses and newborns worldwide, and individuals afflicted with syphilis have an enhanced risk for HIV transmission and acquisition. The global disease burden of syphilis and failure of decades of public health efforts to stem the incidence of disease highlight the need for an effective syphilis vaccine. Although challenges associated with T. pallidum research have impeded understanding of this pathogen, the existence of a relevant animal model has enabled insight into the correlates of disease protection. Complete protection against infection has been achieved in the animal model using an extended immunization regimen of γ-irradiated T. pallidum, demonstrating the importance of treponemal surface components in generation of protective immunity and the feasibility of syphilis vaccine development. Syphilis is a prime candidate for development of a successful vaccine due to the (1) research community's accumulated knowledge of immune correlates of protection; (2) existence of a relevant animal model that enables effective pre-clinical analyses; (3) universal penicillin susceptibility of T. pallidum which enhances the attractiveness of clinical vaccine trials; and (4) significant public health benefit a vaccine would have on reduction of infectious/congenital syphilis and HIV rates. Critical personnel, research and market gaps need to be addressed before the goal of a syphilis vaccine can be realized, including recruitment of additional researchers to the T. pallidum research field with a proportional increase in research funding

  2. Organizing the HIV vaccine development effort.

    PubMed

    Voronin, Yegor; Snow, William

    2013-09-01

    To describe and compare the diverse organizational structures and funding mechanisms applied to advance HIV preventive vaccine research and development and to help explain and inform evolving infrastructures and collaborative funding models. On the basis of models that have been tried, improved or abandoned over three decades, the field seems to have settled into a relatively stable set of diverse initiatives, each with its own organizational signature. At the same time, this set of organizations is forging cross-organizational collaborations, which promise to acquire newly emergent beneficial properties. Strong motivation to expedite HIV vaccine R&D has driven a diversity of customized and inventive organizational approaches, largely government and foundation funded. Although no one approach has proven a panacea, the field has evolved into a constellation of often overlapping organizations that complement or reinforce one another. The Global HIV Vaccine Enterprise, a responsive, rapidly evolving loose infrastructure, is an innovative collaboration to catalyze that evolution.

  3. Organizing the HIV Vaccine Development Effort

    PubMed Central

    Voronin, Yegor; Snow, William

    2014-01-01

    Purpose of Review Describe and compare the diverse organizational structures and funding mechanisms applied to advance HIV preventive vaccine research and development, to help explain and inform evolving infrastructures and collaborative funding models. Recent Findings Based on models that have been tried, improved or abandoned over three decades, the field seems to have settled into a relatively stable set of diverse initiatives, each with its own organizational signature. At the same time, this set of organizations is forging cross-organizational collaborations, which promise to acquire newly emergent beneficial properties. Summary Strong motivation to expedite HIV vaccine R&D has driven a diversity of customized and inventive organizational approaches, largely government and foundation funded. While no one approach has proven a panacea, the field has evolved into a constellation of often overlapping organizations that complement or reinforce one another. The Global HIV Vaccine Enterprise, a responsive, rapidly evolving loose infrastructure, is an innovative collaboration to catalyze that evolution. PMID:23924997

  4. Strengthening TB infection control in specialized health facilities in Romania--using a participatory approach.

    PubMed

    Turusbekova, N; Popa, C; Dragos, M; van der Werf, M J; Dinca, I

    2016-02-01

    In 2012, the tuberculosis (TB) notification rate among Romanian TB facility doctors and nurses was 7.2 times higher than in the general population. This indicates that transmission is ongoing inside TB facilities and that TB infection control measures are insufficient. To help prevent nosocomial TB transmission a project was implemented that aimed at providing nationwide tailor-made technical assistance in TB infection control (TB-IC) in TB treatment facilities, including the development of TB infection control plans. The objective of the present article is to describe the implementation of the project and to discuss successes and challenges. The project was an implementation study using two methods of evaluation: (1) a cross sectional questionnaire study; and (2) collection of information, during the training, on challenges related to infection control and to the project implementation. The project team developed a TB facility infection control (TB-IC) plan template, together with the Romanian experts. The template was discussed and agreed upon with the experts at a meeting and thereafter distributed by email to all TB facilities. Afterwards, a training of trainers (TOT) seminar was organized which included the provision of information about different training methods, as well as information about TB-IC. The TOT was followed by training for key TB-IC providers. Information about use of the TB-IC template was gathered through a self-administered questionnaire sent to all participants of the expert meeting and the training (42 people). Additionally, non-systematized discussions were held on broader challenges in TB-IC implementation during the training. Within the project 42 key TB-IC service providers were trained in TB-IC, including 9 who were trained at a TOT seminar. The trainees were specialists working at the national level, such as country TB coordinators, or at the TB facility level: TB doctors, epidemiologists, laboratory specialists and maintenance

  5. Beyond empiricism: informing vaccine development through innate immunity research.

    PubMed

    Levitz, Stuart M; Golenbock, Douglas T

    2012-03-16

    Although a great public heath success, vaccines provide suboptimal protection in some patient populations and are not available to protect against many infectious diseases. Insights from innate immunity research have led to a better understanding of how existing vaccines work and have informed vaccine development. New adjuvants and delivery systems are being designed based upon their capacity to stimulate innate immune sensors and target antigens to dendritic cells, the cells responsible for initiating adaptive immune responses. Incorporating these adjuvants and delivery systems in vaccines can beneficially alter the quantitative and qualitative nature of the adaptive immune response, resulting in enhanced protection. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. TB Is Back.

    ERIC Educational Resources Information Center

    Natale, Jo Anna

    1992-01-01

    The reemergence of tuberculosis, particularly of new drug-resistant strains, points up the need for well-coordinated school health programs. Immigration effects, growing populations of HIV-infected persons, and relaxed screening procedures are partly responsible for TB's reemergence. Two sidebars offer advice on coping with TB at school and…

  7. The introduction of new vaccines into developing countries. IV: Global Access Strategies.

    PubMed

    Mahoney, Richard T; Krattiger, Anatole; Clemens, John D; Curtiss, Roy

    2007-05-16

    This paper offers a framework for managing a comprehensive Global Access Strategy for new vaccines in developing countries. It is aimed at strengthening the ability of public-sector entities to reach their goals. The Bill and Melinda Gates Foundation and The Rockefeller Foundation have been leaders in stimulating the creation of new organizations - public/private product development partnerships (PDPs) - that seek to accelerate vaccine development and distribution to meet the health needs of the world's poor. Case studies of two of these PDPs - the Salmonella Anti-pneumococcal Vaccine Program and the Pediatric Dengue Vaccine Initiative - examine development of such strategies. Relying on the application of innovation theory, the strategy leads to the identification of six Components of Innovation which cover all aspects of the vaccine innovation process. Appropriately modified, the proposed framework can be applied to the development and introduction of other products in developing countries including drugs, and nutritional and agricultural products.

  8. Nanoparticle based tailoring of adjuvant function: the role in vaccine development.

    PubMed

    Prashant, Chandravilas Keshvan; Kumar, Manoj; Dinda, Amit Kumar

    2014-09-01

    Vaccination is one of the most powerful therapeutic tools for prevention and management of various infective and non-infective diseases including malignancy. Mass vaccination is a great strategy for eradicating major infectious diseases throughout the world like small pox. Application of nanotechnology for antigen delivery is a unique area of research and development which can change the vaccination strategy and policy in future. Nanocarriers can enhance antigen presentation including modulation of antigen processing pathways according to the specific need. The current review explores the pros and cons of application of different nanomaterials for antigen presentation and vaccine development.

  9. Neutron spectroscopic study of crystal field excitations in Tb 2Ti 2O 7 and Tb 2Sn 2O 7

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, J.; Fritsch, Katharina; Hao, Z.

    2014-04-01

    We present time-of-flight inelastic neutron scattering measurements at low temperature on powder samples of the magnetic pyrochlore oxides Tb 2Ti 2O 7 and Tb 2Sn 2O 7. These two materials possess related, but different ground states, with Tb 2Sn 2O 7 displaying "soft" spin ice order below T N approx 0.87 K, while Tb 2Ti 2O 7 enters a hybrid, glassy-spin ice state below T g approx 0.2 K. Our neutron measurements, performed at T = 1.5 K and 30 K, probe the crystal field states associated with the J = 6 states of Tb 3+ within the appropriate Fd3-barmmore » pyrochlore environment. These crystal field states determine the size and anisotropy of the Tb 3+ magnetic moment in each material's ground state, information that is an essential starting point for any description of the low temperature phase behavior and spin dynamics in Tb 2Ti 2O 7 and Tb 2Sn 2O 7. While these two materials have much in common, the cubic stanate lattice is expanded compared to the cubic titanate lattice. As our measurements show, this translates into a factor of approx 2 increase in the crystal field bandwidth of the 2J +1 = 13 states in Tb 2Ti 2O 7 compared with Tb 2Sn 2O 7. Our results are consistent with previous measurements on crystal field states in Tb 2Sn 2O 7, wherein the ground state doublet corresponds primarily to mJ = {vert_bar}+-5> and the first excited state doublet to mJ = {vert_bar}+-4>. In contrast, our results on Tb 2Ti 2O 7 differ markedly from earlier studies, showing that the ground state doublet corresponds to a significant mixture of mJ = {vert_bar}+-5>, mJ = {vert_bar}+-4> and mJ = {vert_bar}+-2>, while the first excited state doublet corresponds to a mixture of mJ = {vert_bar}+-4>, mJ = {vert_bar}+-5> and mJ = {vert_bar}+-1>. We discuss these results in the context of proposed mechanisms for the failure of Tb 2Ti 2O 7 to develop conventional long range order down to 50 mK.« less

  10. Overview of dendritic cell-based vaccine development for leishmaniasis.

    PubMed

    Bagirova, M; Allahverdiyev, A M; Abamor, E S; Ullah, I; Cosar, G; Aydogdu, M; Senturk, H; Ergenoglu, B

    2016-11-01

    Leishmaniasis is one of the most serious vector-borne diseases in the world and is distributed over 98 countries. It is estimated that 350 million people are at risk for leishmaniasis. There are three different generation of vaccines that have been developed to provide immunity and protection against leishmaniasis. However, their use has been limited due to undesired side effects. These vaccines have also failed to provide effective and reliable protection and, as such, currently, there is no safe and effective vaccine for leishmaniasis. Dendritic cells (DCs) are a unique population of cells that come from bone marrow and become specialized to take up, process and present antigens to helper T cells in a mechanism similar to macrophages. By considering these significant features, DCs stimulated with different kinds of Leishmania antigens have been used in recent vaccine studies for leishmaniasis with promising results so far. In this review, we aim to review and combine the latest studies about this issue after defining potential problems in vaccine development for leishmaniasis and considering the importance of DCs in the immunopathogenesis of the disease. © 2016 John Wiley & Sons Ltd.

  11. The state-of-the-art of approved and under-development cholera vaccines.

    PubMed

    Pastor, M; Pedraz, J L; Esquisabel, A

    2013-08-28

    Cholera remains a huge public health problem. Although in 1894, the first cholera vaccination was reported, an ideal vaccine that meets all the requirements of the WHO has not yet been produced. Among the different approaches used for cholera vaccination, attenuated vaccines represent a major category; these vaccines are beneficial in being able to induce a strong protective response after a single administration. However, they have possible negative effects on immunocompromised patient populations. Both the licensed CVD103-HgR and other vaccine approaches under development are detailed in this article, such as the Vibrio cholerae 638 vaccine candidate, Peru-15 or CholeraGarde(®) and the VA1.3, VA1.4, IEM 108 VCUSM2 and CVD 112 vaccine candidates. In another strategy, killed V. cholerae vaccines have been developed, including Dukoral(®), mORCAX(®) and Sanchol™. The killed vaccines are already sold, and they have successfully demonstrated their potential to protect populations in endemic areas or after natural disasters. However, these vaccines do not fulfill all the requirements of the WHO because they fail to confer long-term protection, are not suitable for children under two years, require more than a single dose and require a distribution chain with cold storage. Lastly, other vaccine strategies under development are summarized in this review. Among these strategies, vaccine candidates based on alternative drug delivery systems that have been reported lately in the literature are discussed, such as microparticles, proteoliposomes, LPS subunits, DNA vaccines and rice seeds containing toxin subunits. Preliminary results reported by many groups working on alternative delivery systems for cholera vaccines demonstrate the importance of new technologies in addressing old problems such as cholera. Although a fully ideal vaccine has not yet been designed, promising steps have been reported in the literature resulting in hope for the fight against cholera

  12. A multi-antigenic MVA vaccine increases efficacy of combination chemotherapy against Mycobacterium tuberculosis

    PubMed Central

    Coupet, Charles-Antoine; Gouanvic, Marie; Schmitt, Doris; Ray, Aurélie; Hoffmann, Chantal; Schultz, Huguette; Tyagi, Sandeep; Soni, Heena; Converse, Paul J.; Arias, Lilibeth; Kleinpeter, Patricia; Sansas, Benoît; Mdluli, Khisimuzi; Vilaplana, Cristina; Cardona, Pere-Joan; Nuermberger, Eric; Marchand, Jean-Baptiste; Silvestre, Nathalie; Inchauspé, Geneviève

    2018-01-01

    Despite the existence of the prophylactic Bacille Calmette-Guérin (BCG) vaccine, infection by Mycobacterium tuberculosis (Mtb) remains a major public health issue causing up to 1.8 million annual deaths worldwide. Increasing prevalence of Mtb strains resistant to antibiotics represents an urgent threat for global health that has prompted a search for alternative treatment regimens not subject to development of resistance. Immunotherapy constitutes a promising approach to improving current antibiotic treatments through engagement of the host’s immune system. We designed a multi-antigenic and multiphasic vaccine, based on the Modified Vaccinia Ankara (MVA) virus, denoted MVATG18598, which expresses ten antigens classically described as representative of each of different phases of Mtb infection. In vitro analysis coupled with multiple-passage evaluation demonstrated that this vaccine is genetically stable, i.e. fit for manufacturing. Using different mouse strains, we show that MVATG18598 vaccination results in both Th1-associated T-cell responses and cytolytic activity, targeting all 10 vaccine-expressed Mtb antigens. In chronic post-exposure mouse models, MVATG18598 vaccination in combination with an antibiotic regimen decreases the bacterial burden in the lungs of infected mice, compared with chemotherapy alone, and is associated with long-lasting antigen-specific Th1-type T cell and antibody responses. In one model, co-treatment with MVATG18598 prevented relapse of the disease after treatment completion, an important clinical goal. Overall, results demonstrate the capacity of the therapeutic MVATG18598 vaccine to improve efficacy of chemotherapy against TB. These data support further development of this novel immunotherapeutic in the treatment of Mtb infections. PMID:29718990

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

    PubMed

    Khurana, Surender

    2018-04-27

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

  14. Comparison of the Sensitivity of QuantiFERON-TB Gold In-Tube and T-SPOT.TB According to Patient Age.

    PubMed

    Bae, Won; Park, Kyoung Un; Song, Eun Young; Kim, Se Joong; Lee, Yeon Joo; Park, Jong Sun; Cho, Young-Jae; Yoon, Ho Il; Yim, Jae-Joon; Lee, Choon-Taek; Lee, Jae Ho

    2016-01-01

    Currently, there are two types of interferon-gamma release assays (IGRAs) in use for the detection of tuberculosis (TB) infection, the QuantiFERON-TB Gold In-Tube test (GFT-GIT) and T-SPOT.TB. Owing to contradictory reports regarding whether the results of these IGRAs are affected by the age of the patient, we aimed to determine if these two tests have age-related differences in sensitivity. We retrospectively reviewed the medical records of diagnosed TB patients who were tested using either QFT-GIT or T-SPOT.TB from February 2008 to December 2013. The positivity of the two tests was analyzed and compared with true TB infection, which was defined as active TB based on either a positive Mycobacterium culture or a positive TB polymerase chain reaction. The QFT-GIT group included 192 TB patients, and the T-SPOT.TB group included 212 TB patients. Of the patients with pulmonary TB, 76 (39.6%) were in the QFT-GIT group and 143 (67.5%) in the T-SPOT.TB group. The overall sensitivity was 80.2% for QFT-GIT and 91.0% for T.SPOT.TB. The sensitivities of QFT-GIT and T-SPOT.TB according to age group were as follows: <29 years, 93.3% and 96.7%; 30-49 years, 86.5% and 94.7%; 50-69 years, 76.8% and 87.5%; and >70 years, 68.3% and 85.7%, respectively. The trend of age-related changes in sensitivity was significant for both QFT-GIT (p = 0.004) and T.SPOT.TB (p = 0.039). However, only QFT-GIT was significantly related to age in the multivariate analysis. QFT-GIT, but not T-SPOT.TB, was significantly affected by patient age.

  15. The Density Code for the Development of a Vaccine?

    PubMed Central

    Cheng, Wei

    2016-01-01

    The development of prophylactic vaccines remains largely empirical in nature and rarely have general rules been applied in the strategic decision and the formulation of a viral vaccine. Currently there are a total of 15 virus agents from 12 unique virus families with vaccines licensed by the US Food and Drug Administration. Extensive structural information on these viral particles and potential mechanisms of protection are available for the majority of these virus pathogens and their respective vaccines. Here I review the quantitative features of these viral surface antigens in relation to the molecular mechanisms of B cell activation, and point out a potential correlation between the density of immunogenic proteins displayed on the surface of the vaccine antigen carrier and the success of a vaccine. These features help us understand the humoral immunity induced by viral vaccines on a quantitative ground and re-emphasize the importance of antigen density on the activation of the immune system. Although the detailed mechanisms behind this phenomenon remain to be explored, it implies that both the size of antigen carriers and the density of immunogenic proteins displayed on these carriers are important parameters that may need to be optimized for the formulation of a vaccine. PMID:27649885

  16. Challenges and opportunities in RSV vaccine development: Meeting report from FDA/NIH workshop.

    PubMed

    Roberts, Jeffrey N; Graham, Barney S; Karron, Ruth A; Munoz, Flor M; Falsey, Ann R; Anderson, Larry J; Marshall, V; Kim, Sonnie; Beeler, Judy A

    2016-09-22

    Respiratory syncytial virus (RSV) is the most common cause of serious acute lower respiratory illness in infants and young children and a significant cause of disease burden in the elderly and immunocompromised. There are no licensed RSV vaccines to address this significant public health need. While advances in vaccine technologies have led to a recent resurgence in RSV vaccine development, the immune correlates of protection against RSV and the immunology of vaccine-associated enhanced respiratory disease (ERD) remain poorly understood. FDA's Center for Biologics Evaluation and Research (CBER) and NIH's National Institute of Allergy and Infectious Diseases (NIAID) organized and co-sponsored an RSV Vaccines Workshop in Bethesda, Maryland on June 1 and 2, 2015. The goal of the conference was to convene scientists, regulators, and industry stakeholders to discuss approaches to RSV vaccine development within the context of three target populations - infants and children, pregnant women, and individuals >60years of age. The agenda included topics related to RSV vaccine development in general, as well as considerations specific to each target population, such as clinical and serological endpoints. The meeting focused on vaccine development for high income countries (HIC), because issues relevant to vaccine development for low and middle income countries (LMIC) have been discussed in other forums. This manuscript summarizes the discussion of clinical, scientific, and regulatory perspectives, research gaps, and lessons learned. Copyright © 2016.

  17. Geneva-Seattle collaboration in support of developing country vaccine manufacturing.

    PubMed

    Stevenson, Michael A

    2018-04-01

    Vaccines were once produced almost exclusively by state-supported entities. While they remain essential tools for public health protection, the majority of the world's governments have allowed industry to assume responsibility for this function. This is significant because while the international harmonisation of quality assurance standards have effectively increased vaccine safety, they have also reduced the number of developing country vaccine producers, and Northern multinational pharmaceutical companies have shown little interest in offering the range of low-priced products needed in low and middle-income-country contexts. This article examines how public-private collaboration is relevant to contemporary efforts aimed at strengthening developing country manufacturers' capacity to produce high-quality, low-priced vaccines. Specifically, it casts light on the important and largely complimentary roles of the World Health Organization, The Bill and Melinda Gates Foundation, and the Seattle-based non-profit PATH, in this process. The take away message is that external support remains critical to ensuring that developing country vaccine manufacturers have the tools needed to produce for both domestic and global markets, and the United Nations supply chain, and collaboration at the public-private interface is driving organisational innovation focused on meeting these goals.

  18. Human-animal chimeras for vaccine development: an endangered species or opportunity for the developing world?

    PubMed Central

    2010-01-01

    Background In recent years, the field of vaccines for diseases such as Human Immunodeficiency Virus (HIV) which take a heavy toll in developing countries has faced major failures. This has led to a call for more basic science research, and development as well as evaluation of new vaccine candidates. Human-animal chimeras, developed with a 'humanized' immune system could be useful to study infectious diseases, including many neglected diseases. These would also serve as an important tool for the efficient testing of new vaccine candidates to streamline promising candidates for further trials in humans. However, developing human-animal chimeras has proved to be controversial. Discussion Development of human-animal chimeras for vaccine development has been slowed down because of opposition by some philosophers, ethicists and policy makers in the west-they question the moral status of such animals, and also express discomfort about transgression of species barriers. Such opposition often uses a contemporary western world view as a reference point. Human-animal chimeras are often being created for diseases which cause significantly higher morbidity and mortality in the developing world as compared to the developed world. We argue in our commentary that given this high disease burden, we should look at socio-cultural perspectives on human-animal chimera like beings in the developing world. On examination, it's clear that such beings have been part of mythology and cultural descriptions in many countries in the developing world. Summary To ensure that important research on diseases afflicting millions like malaria, HIV, Hepatitis-C and dengue continues to progress, we recommend supporting human-animal chimera research for vaccine development in developing countries (especially China and India which have growing technical expertise in the area). The negative perceptions in some parts of the west about human-animal chimeras can be used as an opportunity for nurturing

  19. Development and psychometric testing of the Knowledge, Attitudes and Practices (KAP) questionnaire among student Tuberculosis (TB) Patients (STBP-KAPQ) in China.

    PubMed

    Fan, Yahui; Zhang, Shaoru; Li, Yan; Li, Yuelu; Zhang, Tianhua; Liu, Weiping; Jiang, Hualin

    2018-05-08

    TB outbreaking in schools is extremely complex, and presents a major challenge for public health. Understanding the knowledge, attitudes and practices among student TB patients in such settings is fundamental when it comes to decreasing future TB cases. The objective of this study was to develop a Knowledge, Attitudes and Practices Questionnaire among Student Tuberculosis Patients (STBP-KAPQ), and evaluate its psychometric properties. This study was conducted in three stages: item construction, pilot testing in 10 student TB patients and psychometric testing, including reliability and validity. The item pool for the questionnaire was compiled from literature review and early individual interviews. The questionnaire items were evaluated by the Delphi method based on 12 experts. Reliability and validity were assessed using student TB patients (n = 416) and healthy students (n = 208). Reliability was examined with internal consistency reliability and test-retest reliability. Content validity was calculated by content validity index (CVI); Construct validity was examined using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA); The Public Tuberculosis Knowledge, Attitudes and Practices Questionnaire (PTB-KAPQ) was applied to evaluate criterion validity; As concerning discriminant validity, T-test was performed. The final STBP-KAPQ consisted of three dimensions and 25 items. Cronbach's α coefficient and intraclass correlation coefficient (ICC) was 0.817 and 0.765, respectively. Content validity index (CVI) was 0.962. Seven common factors were extracted by principal factor analysis and varimax rotation, with a cumulative contribution of 66.253%. The resulting CFA model of the STBP-KAPQ exhibited an appropriate model fit (χ2/df = 1.74, RMSEA = 0.082, CFI = 0.923, NNFI = 0.962). STBP-KAPQ and PTB-KAPQ had a strong correlation in the knowledge part, and the correlation coefficient was 0.606 (p < 0.05). Discriminant

  20. [USE OF QuantiFERON-TB Gold in Tube AND T-SPOT.TB FOR DIAGNOSING PATIENTS WITH SUSPECTED PULMONARY TUBERCULOSIS].

    PubMed

    Okimoto, Niro; Kurihara, Takeyuki; Miyashita, Naoyuki

    2016-04-01

    We analyzed the use of QFT-TB Gold in Tube and T-SPOT.TB in diagnosing patients with suspected pulmonary tuberculosis. We evaluated 122 patients with suspected pulmonary tuberculosis (where chest X-ray showed consolidation or. tumor shadow in predilection sites of pulmonary tuberculosis and through contact investigation). QFT-TB Gold and T-SPOT.TB were performed for all the patients. The positive response rate and history of pulmonary tuberculosis in patients who showed positive results for the tests were evaluated. Ninteen patients showed positive results for QFT-TB Gold, and 9, for T-SPOT.TB. Four patients showed positive results for QFT-TB Gold, and 3, for T-SPOT.TB in 4 patients with active tuberculosis. The patients without active tuberculosis whose IGRAs were positive (old pulmonary tuberculosis, Mycobacterium avium cmplex, pneumonia, lung cancer, pulmonary sequestration, bronchiectasis) had a past history of pulmonary tuberculosis. The positive result rate of QFT?-TB Gold was higher than that of T-SPOT.TB in the subjects with suspected pulmonary tuberculosis. We think that QFT-TB Gold reflected the past history of pulmonary tuberculosis.

  1. Increased TNF-alpha/IFN-gamma/IL-2 and decreased TNF-alpha/IFN-gamma production by central memory T cells are associated with protective responses against bovine tuberculosis following BCG vaccination

    USDA-ARS?s Scientific Manuscript database

    Central memory T cells (Tcm’s) and polyfunctional CD4 T responses contribute to vaccine-elicited protection with both human and bovine tuberculosis (TB); however, their combined role in protective immunity to TB is unclear. To address this question, we evaluated polyfunctional cytokine responses by ...

  2. A review of licensed viral vaccines, some of their safety concerns, and the advances in the development of investigational viral vaccines.

    PubMed

    Huang, David B; Wu, Jashin J; Tyring, Stephen K

    2004-10-01

    Viral vaccines could be considered among the most important medical achievements of the 20th century. They have prevented much suffering and saved many lives. Although some curative antiviral drugs exist, we desperately depend on efforts by academic, governmental and industrial scientists in the advancement of viral vaccines in the prevention and control of infectious diseases. In the next decade, we hope to see advancement in the development of current and investigational viral vaccines against childhood and adult infections. In this article, we will review the licensed viral vaccines, some of their safety concerns, and the advances in the development of investigational viral vaccines.

  3. Motors of influenza vaccination uptake and vaccination advocacy in healthcare workers: Development and validation of two short scales.

    PubMed

    Vallée-Tourangeau, Gaëlle; Promberger, Marianne; Moon, Karis; Wheelock, Ana; Sirota, Miroslav; Norton, Christine; Sevdalis, Nick

    2017-09-25

    Healthcare workers (HCWs) are an important priority group for vaccination against influenza, yet, flu vaccine uptake remains low among them. Psychosocial studies of HCWs' decisions to get vaccinated have commonly drawn on subjective expected utility models to assess predictors of vaccination, assuming HCWs' choices result from a rational information-weighing process. By contrast, we recast those decisions asa commitment to vaccination and we aimed to understand why HCWs may want to (rather than believe they need to) get vaccinated against the flu. This article outlines the development and validation of a 9-item measure of cognitive empowerment towards flu vaccination (MoVac-flu scale) and an 11-item measure of cognitive empowerment towards vaccination advocacy. Both scales were administered to 784 frontline NHS HCWs with direct patient contact between June 2014 and July 2015. The scales exhibited excellent reliability and a clear unidimensional factor structure. An examination of the nomological network of the cognitive empowerment construct in relation to HCWs' vaccination against the flu revealed that this construct was distinct from traditional measures of risk perception and the strongest predictor of HCWs' decisions to vaccinate. Similarly, cognitive empowerment in relation to vaccination advocacy was a strong predictor of HCWs' engagement with vaccination advocacy. These findings suggest that the cognitive empowerment construct has important implications for advancing our understanding of HCWs' decisions to vaccinate as well as their advocacy behavior. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Vaccine production training to develop the workforce of foreign institutions supported by the BARDA influenza vaccine capacity building program.

    PubMed

    Tarbet, E Bart; Dorward, James T; Day, Craig W; Rashid, Kamal A

    2013-03-15

    In the event of an influenza pandemic, vaccination will be the best method to limit virus spread. However, lack of vaccine biomanufacturing capacity means there will not be enough vaccine for the world's population. The U.S. Department of Health and Human Services, Biomedical Advanced Research and Development Authority (BARDA) provides support to the World Health Organization to enhance global vaccine production capacity in developing countries. However, developing a trained workforce in some of those countries is necessary. Biomanufacturing is labor-intensive, requiring unique skills not found in traditional academic programs. Employees must understand the scientific basis of biotechnology, operate specialized equipment, and work in an environment regulated by good manufacturing practices (cGMP). Therefore, BARDA supported development of vaccine biomanufacturing training at Utah State University. The training consisted of a three-week industry-focused course for participants from institutions supported by the BARDA and WHO influenza vaccine production capacity building program. The curriculum was divided into six components: (1) biosafety, (2) cell culture and growth of cells in bioreactors, (3) virus assays and inactivation, (4) scale-up strategies, (5) downstream processing, and (6) egg- and cell-based vaccine production and cGMP. Lectures were combined with laboratory exercises to provide a balance of theory and hands-on training. The initial course included sixteen participants from seven countries including: Egypt, Romania, Russia, Serbia, South Korea, Thailand, and Vietnam. The participant's job responsibilities included: Production, Quality Control, Quality Assurance, and Research; and their education ranged from bachelors to doctoral level. Internal course evaluations utilized descriptive methods including surveys, observation of laboratory activities, and interviews with participants. Generally, participants had appropriate academic backgrounds, but

  5. Clinical development of placental malaria vaccines and immunoassays harmonization: a workshop report.

    PubMed

    Chêne, Arnaud; Houard, Sophie; Nielsen, Morten A; Hundt, Sophia; D'Alessio, Flavia; Sirima, Sodiomon B; Luty, Adrian J F; Duffy, Patrick; Leroy, Odile; Gamain, Benoit; Viebig, Nicola K

    2016-09-17

    Placental malaria caused by Plasmodium falciparum infection constitutes a major health problem manifesting as severe disease and anaemia in the mother, impaired fetal development, low birth weight or spontaneous abortion. Prevention of placental malaria currently relies on two key strategies that are losing efficacy due to spread of resistance: long-lasting insecticide-treated nets and intermittent preventive treatment during pregnancy. A placental malaria vaccine would be an attractive, cost-effective complement to the existing control tools. Two placental malaria vaccine candidates are currently in Phase Ia/b clinical trials. During two workshops hosted by the European Vaccine Initiative, one in Paris in April 2014 and the other in Brussels in November 2014, the main actors in placental malaria vaccine research discussed the harmonization of clinical development plans and of the immunoassays with a goal to define standards that will allow comparative assessment of different placental malaria vaccine candidates. The recommendations of these workshops should guide researchers and clinicians in the further development of placental malaria vaccines.

  6. Using a prime and pull approach, lentivector vaccines expressing Ag85A induce immunogenicity but fail to induce protection against Mycobacterium bovis bacillus Calmette–Guérin challenge in mice

    PubMed Central

    Britton, Gary; MacDonald, Douglas C; Brown, Jeremy S; Collins, Mary K; Goodman, Anna L

    2015-01-01

    Although bacillus Calmette–Guérin (BCG) is an established vaccine with excellent efficacy against disseminated Mycobacterium tuberculosis infection in young children, efficacy in adults suffering from respiratory tuberculosis (TB) is suboptimal. Prime-boost viral vectored vaccines have been shown to induce effective immune responses and lentivectors (LV) have been shown to improve mucosal immunity in the lung. A mucosal boost to induce local immunogenicity is also referred to as a ‘pull’ in a prime and pull approach, which has been found to be a promising vaccine strategy. The majority of infants worldwide receive BCG immunization through current vaccine protocols. We therefore aimed to investigate the role of a boost (or pull) immunization with an LV vaccine expressing the promising TB antigen (Ag85A). We immunized BALB/c mice subcutaneously with BCG or an LV vaccine expressing a nuclear factor-κB activator vFLIP together with Ag85A (LV vF/85A), then boosted with intranasal LV vF/85A. Prime and pull immunization with LV85A induced significantly enhanced CD8+ and CD4+ T-cell responses in the lung, but did not protect against intranasal BCG challenge. In contrast, little T-cell response in the lung was seen when the prime vaccine was BCG, and intranasal vF/85A provided no additional protection against mucosal BCG infection. Our study demonstrates that not all LV prime and pull approaches may be successful against TB in man and careful antigen and immune activator selection is therefore required. PMID:26095282

  7. Development of chimeric candidate vaccine against HPV18: a proof of concept.

    PubMed

    Wahiduzzaman, Mohammed; Sharma, Chandresh; Dey, Bindu; Bhatla, Neerja; Singh, Neeta

    2015-06-01

    Human papillomaviruses (HPVs) are prerequisite for the development of cervical cancer, with HPV16 and HPV18 being the most prevalent. Despite the fact that two prophylactic vaccines against HPVs are in the market, wide-scale application of the vaccine in developing countries is a major problem as far as cost of the vaccine and lack of therapeutic efficacy are concerned. Hence, the aim of our study was to develop HPV18 L1E7 chimeric virus-like particles (CVLPs) vaccine candidate possessing both, prophylactic and therapeutic potential against HPV18-associated cervical cancer. In this study, we have developed a potential candidate vaccine against HPV18 involving HPV18 L1E7 CVLPs, which was expressed in E. coli and assembled in vitro. These CVLPs were able to induce a neutralizing antibody response as well as a cell-mediated immune response in mice.

  8. Botulinum neurotoxin vaccines: Past history and recent developments.

    PubMed

    Rusnak, Janice M; Smith, Leonard A

    2009-12-01

    Botulinum toxin may cause a neuroparalytic illness that may result in respiratory failure and require prolonged mechanical ventilation. As medical resources needed for supportive care of botulism in a bioterrorist event may quickly overwhelm the local healthcare systems, biodefense research efforts have been directed towards the development of a vaccine to prevent botulism. While human botulism has been caused only by toxin serotypes A, B, and E (rarely serotype F), all seven known immunologically distinct toxin serotypes (A - G) may potentially cause intoxication in humans from a bioterrorist event. A pentavalent (ABCDE) botulinum toxoid (PBT) has been administered as an investigation new drug (IND) to at-risk individuals for nearly 50 years. Due to declining immunogenicity of the PBT, research efforts have been directed at development of both improved (less local reactogenicity) botulinum toxoids and recombinant vaccines as potential vaccine candidates to replace the PBT.

  9. Extensively Drug-resistant Tuberculosis (XDR-TB): A daunting challenge to the current End TB Strategy and policy recommendations.

    PubMed

    Rahman, Md Arifur; Sarkar, Atanu

    2017-07-01

    Extensively Drug-resistant Tuberculosis (XDR-TB) has emerged as one of the most formidable challenges to the End TB Strategy that has targeted a 95% reduction in TB deaths and 90% reduction in cases by 2035. Globally, there were an estimated 55,100 new XDR-TB cases in 2015 in 117 countries. However, only one in 30 XDR-TB cases had been reported so far. Drug susceptibility test (DST) is the mainstay for diagnosing XDR-TB, but the lack of laboratory facilities in the resource-limited endemic countries limit its uses. A few new drugs including bedaquiline and delamanid, have the potential to improve the efficiency of XDR-TB treatment, but the drugs have been included in 39 countries only. The costs of XDR-TB treatment are several folds higher than that of the MDR-TB. Despite the financing from the donors, there is an urgent need to fill the current funding gap of US$ 2 billion to ensure effective treatment and robust surveillance. In the review article we have addressed current update on XDR-TB, including surveillance, diagnosis and the interventions needed to treat and limit its spread, emphasis on extensive financial support for implementing of current recommendations to meet the goals of End TB Strategy. Copyright © 2017 Tuberculosis Association of India. Published by Elsevier B.V. All rights reserved.

  10. Concordant or discordant results by the tuberculin skin test and the quantiFERON-TB test in children reflect immune biomarker profiles.

    PubMed

    Dhanasekaran, S; Jenum, S; Stavrum, R; Ritz, C; Kenneth, J; Vaz, M; Doherty, T M; Grewal, H M S

    2014-01-01

    The tuberculin skin test (TST) and QuantiFERON-TB-Gold-In-tube (QFTGIT) are adjunctive tests used in the diagnosis of pediatric tuberculosis (TB). Neither test can rule out TB; however, a positive test usually triggers preventive treatment in TB contacts aged <5 years. TST and QFTGIT can give divergent results and it is unclear how discordant results should be interpreted in terms of TB risk and preventive treatment. To understand the immune processes underlying concordant or discordant TST and QFTGIT results, we analyzed immune responses in children from Palamaner Taluk in India (a TB-endemic region with routine neonatal BCG vaccination) who were referred to a TB case verification ward on suspicion of TB. Two hundred and ten children aged <3 years were classified according to their TST and QFTGIT results, and their immune responses analyzed by dual-colour-Reverse-Transcriptase-Multiple-Ligation-dependent-Probe-Amplification, using a panel of 45 genes and a 10-plex antigen-specific enzyme-linked immunosorbent assay. We show that immune biomarkers FPR1, TNFRSF1A and interferon (IFN)-γ are upregulated (all P<0.05) in concordant test-positive children, whereas BPI is downregulated (P<0.05). In contrast, SEC14L1 (P=0.034) and Interferon gamma-induced protein 10 (IP-10) (P=0.001) are differentially expressed between the TST+QFTGIT- /TST-QFTGIT+ groups. Known TB exposure was more frequent in concordant positive children and results were consistent with elevated expression of genes associated with inflammatory responses. Children with discordant test results displayed a mixed profile with activation of both pro- and anti-inflammatory markers. TST and/or QFTGIT positivity appears to reflect distinct but overlapping aspects of host immunity.

  11. Developing VISO: Vaccine Information Statement Ontology for patient education.

    PubMed

    Amith, Muhammad; Gong, Yang; Cunningham, Rachel; Boom, Julie; Tao, Cui

    2015-01-01

    To construct a comprehensive vaccine information ontology that can support personal health information applications using patient-consumer lexicon, and lead to outcomes that can improve patient education. The authors composed the Vaccine Information Statement Ontology (VISO) using the web ontology language (OWL). We started with 6 Vaccine Information Statement (VIS) documents collected from the Centers for Disease Control and Prevention (CDC) website. Important and relevant selections from the documents were recorded, and knowledge triples were derived. Based on the collection of knowledge triples, the meta-level formalization of the vaccine information domain was developed. Relevant instances and their relationships were created to represent vaccine domain knowledge. The initial iteration of the VISO was realized, based on the 6 Vaccine Information Statements and coded into OWL2 with Protégé. The ontology consisted of 132 concepts (classes and subclasses) with 33 types of relationships between the concepts. The total number of instances from classes totaled at 460, along with 429 knowledge triples in total. Semiotic-based metric scoring was applied to evaluate quality of the ontology.

  12. Evaluation of vaccines against enteric infections: a clinical and public health research agenda for developing countries

    PubMed Central

    Clemens, John

    2011-01-01

    Enteric infections are a major cause of morbidity and mortality in developing countries. To date, vaccines have played a limited role in public health efforts to control enteric infections. Licensed vaccines exist for cholera and typhoid, but these vaccines are used primarily for travellers; and there are two internationally licensed vaccines for rotavirus, but they are mainly used in affluent countries. The reasons that enteric vaccines are little used in developing countries are multiple, and certainly include financial and political constraints. Also important is the need for more cogent evidence on the performance of enteric vaccines in developing country populations. A partial inventory of research questions would include: (i) does the vaccine perform well in the most relevant settings? (ii) does the vaccine perform well in all epidemiologically relevant age groups? (iii) is there adequate evidence of vaccine safety once the vaccines have been deployed in developing countries? (iv) how effective is the vaccine when given in conjunction with non-vaccine cointerventions? (v) what is the level of vaccine protection against all relevant outcomes? and (vi) what is the expected population level of vaccine protection, including both direct and herd vaccine protective effects? Provision of evidence addressing these questions will help expand the use of enteric vaccines in developing countries. PMID:21893543

  13. Ebola vaccine development plan: ethics, concerns and proposed measures.

    PubMed

    Folayan, Morenike Oluwatoyin; Yakubu, Aminu; Haire, Bridget; Peterson, Kristin

    2016-02-08

    The global interest in developing therapies for Ebola infection management and its prevention is laudable. However the plan to conduct an emergency immunization program specifically for healthcare workers using experimental vaccines raises some ethical concerns. This paper shares perspectives on these concerns and suggests how some of them may best be addressed. The recruitment of healthcare workers for Ebola vaccine research has challenges. It could result in coercion of initially dissenting healthcare workers to assist in the management of EVD infected persons due to mistaken beliefs that the vaccine offers protection. It could also affect equity and justice. For example, where people who are not skilled health care professionals but who provide care to patients infected with Ebola (such as in home care settings) are not prioritized for vaccination. The possibility of study participants contracting Ebola infection despite the use of experimental vaccine, and the standard of care they would receive, needs to be addressed clearly, transparently and formalized as part of the ethics review process. Future access to study products in view of current status of the TRIPS agreement needs to be addressed. Finally, broad stakeholder engagement at local, regional and international levels needs to be promoted using available communication channels to engage local, regional and international support. These same concerns are applicable for current and future epidemics. Successful Ebola vaccine development research requires concerted efforts at public dialogue to address misconceptions, equity and justice in participant selection, and honest discussions about risks, benefits and future access. Public dialogue about Ebola vaccine research plans is crucial and should be conducted by trusted locals and negotiated between communities, researchers and ethics committees in research study sites.

  14. Development of improved pertussis vaccine.

    PubMed

    Rumbo, Martin; Hozbor, Daniela

    2014-01-01

    Rates of infection with Bordetella pertussis, the gram-negative bacterium that causes the respiratory disease called whooping cough or pertussis, have not abated and 16 million cases with almost 200,000 deaths are estimated by the WHO to have occurred worldwide in 2008. Despite relatively high vaccination rates, the disease has come back in recent years to afflict people in numbers not seen since the pre-vaccine days. Indeed, pertussis is now recognized as a frequent infection not only in newborn and infants but also in adults. The disease symptoms also can be induced by the non-vaccine-preventable infection with the close species B. parapertussis for which an increasing number of cases have been reported. The epidemiologic situation and current knowledge of the limitations of pertussis vaccine point out the need to design improved vaccines. Several alternative approaches and their challenges are summarized.

  15. Development of improved pertussis vaccine

    PubMed Central

    Rumbo, Martin; Hozbor, Daniela

    2014-01-01

    Rates of infection with Bordetella pertussis, the gram-negative bacterium that causes the respiratory disease called whooping cough or pertussis, have not abated and 16 million cases with almost 200,000 deaths are estimated by the WHO to have occurred worldwide in 2008. Despite relatively high vaccination rates, the disease has come back in recent years to afflict people in numbers not seen since the pre-vaccine days. Indeed, pertussis is now recognized as a frequent infection not only in newborn and infants but also in adults. The disease symptoms also can be induced by the non-vaccine-preventable infection with the close species B. parapertussis for which an increasing number of cases have been reported. The epidemiologic situation and current knowledge of the limitations of pertussis vaccine point out the need to design improved vaccines. Several alternative approaches and their challenges are summarized. PMID:25424954

  16. TB in Children in the United States

    MedlinePlus

    ... Search Form Controls Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  17. TB control: challenges and opportunities for India.

    PubMed

    Pai, Madhukar; Daftary, Amrita; Satyanarayana, Srinath

    2016-03-01

    India's TB control programme has treated over 19 million patients, but the incidence of TB continues to be high. TB is a major killer and drug-resistant TB is a growing threat. There are several likely reasons, including social conditions and co-morbidities that fuel the TB epidemic: under-investment by the government, weak programme implementation and management, suboptimal quality of care in the private sector, and insufficient advocacy around TB. Fortunately, India possesses the technical know-how, competence and resources to address these challenges. The End TB Strategy by WHO offers India an excellent blueprint to advance the agenda of TB control. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Pastoralism and delay in diagnosis of TB in Ethiopia

    PubMed Central

    Gele, Abdi A; Bjune, Gunnar; Abebe, Fekadu

    2009-01-01

    the only observed predictor for health care providers' delay (aOR. 3.39, CI 1.68–6.83). Conclusion Patient delay observed among pastoralist TB patients in SRS is one of the highest reported so far from developing countries, exceeding two years in some patients. This long patient delay appears to be associated with patient's inadequate knowledge of the disease and distance to health care facility with nomadic pastoralists being the most affected. Regional TB control programmes need to consider the exceptional circumstances of pastoralists, to maximise their access to TB services. PMID:19128498

  19. Risk factors for false-negative T-SPOT.TB assay results in patients with pulmonary and extra-pulmonary TB.

    PubMed

    Pan, Liping; Jia, Hongyan; Liu, Fei; Sun, Huishan; Gao, Mengqiu; Du, Fengjiao; Xing, Aiying; Du, Boping; Sun, Qi; Wei, Rongrong; Gu, Shuxiang; Zhang, Zongde

    2015-04-01

    To investigate the risk factors for false-negative T-SPOT.TB results in patients with pulmonary TB (PTB) and extra-pulmonary TB (EPTB). Patients with suspected TB who underwent valid T-SPOT.TB tests were prospectively enrolled at Beijing Chest Hospital between November 2012 and November 2013. Basic characters and clinical laboratory findings were compared between true-positive and false-negative T-SPOT.TB groups. Of 1928 suspected TB patients, 774 (530 PTB and 244 EPTB) microbiologically/histopathogenically-confirmed patients (636 culture-confirmed) were analyzed. Forty-six PTB patients (8.7%) and 32 EPTB patients (13.1%) had negative T-SPOT.TB results. Multivariate analysis showed that increased age [odds radio (OR) 2.26, 95% confidence interval (CI) 1.11-4.58], over-weight (BMI ≥ 25 kg/m(2), OR 2.43, 95% CI 1.05-5.63), and a longer period of illness before hospitalization (>6 months, OR 2.46, 95% CI 1.24-4.92) were independent risk factors for false-negative T-SPOT.TB results in PTB patients. In EPTB patients, increased age (OR 2.42, 95% CI 1.09-5.35) also showed an independent association with false-negative T-SPOT.TB results. Careful interpretation of negative T-SPOT.TB results is necessary in older patients with suspected PTB or EPTB, and in PTB patients who are over-weight or have had longer periods of illness before hospitalization. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  20. Development and Evaluation of a Pilot Nurse Case Management Model to Address Multidrug-Resistant Tuberculosis (MDR-TB) and HIV in South Africa

    PubMed Central

    Farley, Jason E.; Kelly, Ana M.; Reiser, Katrina; Brown, Maria; Kub, Joan; Davis, Jeane G.; Walshe, Louise; Van der Walt, Martie

    2014-01-01

    Setting Multidrug-resistant tuberculosis (MDR-TB) unit in KwaZulu-Natal, South Africa. Objective To develop and evaluate a nurse case management model and intervention using the tenets of the Chronic Care Model to manage treatment for MDR-TB patients with a high prevalence of human immunodeficiency virus (HIV) co-infection. Design A quasi-experimental pilot programme utilizing a nurse case manager to manage care for 40 hospitalized MDR-TB patients, 70% HIV co-infected, during the intensive phase of MDR-TB treatment. Patients were followed for six months to compare proximal outcomes identified in the model between the pre- and post-intervention period. Results The greatest percent differences between baseline and six-month MDR-TB proximal outcomes were seen in the following three areas: baseline symptom evaluation on treatment initiation (95% improvement), baseline and monthly laboratory evaluations completed per guidelines (75% improvement), and adverse drug reactions acted upon by medical and/or nursing intervention (75% improvement). Conclusion Improvements were identified in guideline-based treatment and monitoring of adverse drug reactions following implementation of the nurse case management intervention. Further study is required to determine if the intervention introduced in this model will ultimately result in improvements in final MDR-TB treatment outcomes. PMID:25405988