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Microbial Biotechnology Sep 2014Bacterial cold water disease (BCWD) is a globally distributed freshwater fish disease caused by the Gram-negative bacterium Flavobacterium psychrophilum. It is a... (Review)
Review
Bacterial cold water disease (BCWD) is a globally distributed freshwater fish disease caused by the Gram-negative bacterium Flavobacterium psychrophilum. It is a particularly devastating infection in fry salmonids and may lead to high levels of mortality. In spite of its economic impact on fish farms, neither the biology of the bacterium nor the bacterium-host interactions are well understood. This review provides a synopsis of the major problems related to critical remaining questions about research into the use of vaccines against F. psychrophilum and the development of a commercial vaccine against this disease. Studies using sera from convalescent rainbow trout have shown the antigenic properties of different proteins such as OmpH, OmpA and FspA, as well as low and high molecular mass lipopolysaccharide of F. psychrophilum, which are potential candidates for subunit vaccines. Inactivated F. psychrophilum bacterins have been successfully tested as vaccines under laboratory conditions by both immersion and intraperitoneal routes. However, the efficacy and the practical usefulness of these preparations still have to be proved. The use of attenuated and wild-type strains to immunize fish showed that these systems offer high levels of protection. Nevertheless, their application clashes with the regulations for environmental protection in many countries. In conclusion, protective vaccines against BCWD are theoretically possible, but substantial efforts still have to be made in order to permit the development of a commercial vaccine.
Topics: Animals; Bacterial Vaccines; Fish Diseases; Fishes; Flavobacteriaceae Infections; Flavobacterium; Treatment Outcome; Vaccines, Attenuated; Vaccines, Inactivated; Vaccines, Subunit
PubMed: 25056179
DOI: 10.1111/1751-7915.12099 -
Frontiers in Immunology 2020Increasing antibiotic resistance in bacteria causing endogenous infections has entailed a need for innovative approaches to therapy and prophylaxis of these infections... (Review)
Review
Increasing antibiotic resistance in bacteria causing endogenous infections has entailed a need for innovative approaches to therapy and prophylaxis of these infections and raised a new interest in vaccines for prevention of colonization and infection by typically antibiotic resistant pathogens. Nevertheless, there has been a long history of failures in late stage clinical development of this type of vaccines, which remains not fully understood. This article provides an overview on present and past vaccine developments targeting nosocomial bacterial pathogens; it further highlights the specific challenges associated with demonstrating clinical efficacy of these vaccines and the facts to be considered in future study designs. Notably, these vaccines are mainly applied to subjects with preexistent immunity to the target pathogen, transient or chronic immunosuppression and ill-defined microbiome status. Unpredictable attack rates and changing epidemiology as well as highly variable genetic and immunological strain characteristics complicate the development. In views of the clinical need, re-thinking of the study designs and expectations seems warranted: first of all, vaccine development needs to be footed on a clear rationale for choosing the immunological mechanism of action and the optimal time point for vaccination, e.g., (1) prevention (or reduction) of colonization vs. prevention of infection and (2) boosting of a preexistent immune response vs. altering the quality of the immune response. Furthermore, there are different, probably redundant, immunological and microbiological defense mechanisms that provide protection from infection. Their interplay is not well-understood but as a consequence their effect might superimpose vaccine-mediated resolution of infection and lead to failure to demonstrate efficacy. This implies that improved characterization of patient subpopulations within the trial population should be obtained by pro- and retrospective analyses of trial data on subject level. Statistical and systems biology approaches could help to define immune and microbiological biomarkers that discern populations that benefit from vaccination from those where vaccines might not be effective.
Topics: Bacteria; Bacterial Infections; Bacterial Vaccines; Cross Infection; Drug Design; Drug Development; Host-Pathogen Interactions; Humans; Vaccination
PubMed: 32849627
DOI: 10.3389/fimmu.2020.01755 -
Experimental & Molecular Medicine Mar 2014Vaccination is one of the most successful applications of immunology and for a long time has depended on parenteral administration protocols. However, recent studies... (Review)
Review
Vaccination is one of the most successful applications of immunology and for a long time has depended on parenteral administration protocols. However, recent studies have pointed to the promise of mucosal vaccination because of its ease, economy and efficiency in inducing an immune response not only systemically, but also in the mucosal compartment where many pathogenic infections are initiated. However, successful mucosal vaccination requires the help of an adjuvant for the efficient delivery of vaccine material into the mucosa and the breaking of the tolerogenic environment, especially in oral mucosal immunization. Given that M cells are the main gateway to take up luminal antigens and initiate antigen-specific immune responses, understanding the role and characteristics of M cells is crucial for the development of successful mucosal vaccines. Especially, particular interest has been focused on the regulation of the tolerogenic mucosal microenvironment and the introduction of the luminal antigen into the lymphoid organ by exploiting the molecules of M cells. Here, we review the characteristics of M cells and the immune regulatory factors in mucosa that can be exploited for mucosal vaccine delivery and mucosal immune regulation.
Topics: Administration, Oral; Animals; Antigens, Bacterial; Antigens, Viral; Bacterial Vaccines; Humans; Immunity, Mucosal; Intestinal Mucosa; Peyer's Patches; Viral Vaccines
PubMed: 24626171
DOI: 10.1038/emm.2013.165 -
Pharmaceutical Medicine Jan 2021The high incidence of error reports received by the US Food and Drug Administration (FDA) involving 2-component vaccines led to collaboration between the United States...
The high incidence of error reports received by the US Food and Drug Administration (FDA) involving 2-component vaccines led to collaboration between the United States Pharmacopeia (USP) and the Institute for Safe Medication Practices (ISMP). This collaborating group sought to further understand errors associated with all 2-component vaccines (i.e. vaccine components provided by the manufacturer in physically separate containers) and to provide safe practice strategies for storing, preparing, dispensing, and administering these vaccines as intended. Fourteen available 2-component vaccines were identified. The ISMP National Vaccine Errors Reporting Program (VERP) and the FDA Vaccine Adverse Event Reporting System (VAERS) were searched from the initiation of each respective reporting system through December 31, 2019. The three vaccines with the most reported reconstitution errors in the VERP and VAERS are Menveo (meningococcal), Pentacel (DTaP, Polio, Haemophilus influenzae type b), and ActHIB [H. influenzae type b (Hib)]. Manufacturers should design labeling and packaging of vaccines to provide ease of storage and fail-safe preparation to prevent 2-component vaccine errors. Implementing risk reduction strategies, such as training healthcare professionals and affixing storage bin labels, remind healthcare professionals to mix the 2-components and facilitate appropriate administration.
Topics: Adverse Drug Reaction Reporting Systems; Bacterial Vaccines; Haemophilus influenzae type b; Meningococcal Vaccines; United States; United States Food and Drug Administration
PubMed: 33151497
DOI: 10.1007/s40290-020-00362-9 -
Human Vaccines & Immunotherapeutics 2018The problem of antimicrobial resistance (AMR) and the associated morbidity and mortality due to antibiotic resistant bacterial pathogens is not new. However, AMR has... (Review)
Review
The problem of antimicrobial resistance (AMR) and the associated morbidity and mortality due to antibiotic resistant bacterial pathogens is not new. However, AMR has been increasing at an alarming rate with appearances of diseases caused by bacteria exhibiting resistance to not just one but multiple classes of antibiotics. The World Health Organization (WHO) supported by governments, health ministries and health agencies has formulated global action plans to combat the rise in AMR, supporting a number of proven initiatives such as antimicrobial stewardship, investments in development of new classes of antibiotics, and educational programs designed to eliminate inappropriate antibiotic use. Vaccines as tools to reduce AMR have historically been under-recognized, yet the positive effect in reducing AMR has been well established. For example Haemophilus influenzae type B (Hib) as well as Streptococcus pneumoniae (pneumococcal) conjugate vaccines have impressive track records in not only preventing life threatening diseases caused by these bacteria, but also reducing antibiotic use and AMR. This paper will describe the drivers of antibiotic use and subsequent development of AMR; it will make the case how existing vaccines are already participating in combatting AMR, describe future prospects for the role of new vaccines in development to reduce AMR, and highlight challenges associated with future vaccine development to combat AMR.
Topics: Anti-Bacterial Agents; Bacterial Infections; Bacterial Vaccines; Drug Development; Drug Resistance, Microbial; Humans
PubMed: 29787323
DOI: 10.1080/21645515.2018.1476814 -
Critical Reviews in Microbiology Nov 2016Gonorrhea is a major, global public health problem for which there is no vaccine. The continuing emergence of antibiotic-resistant strains raises concerns that... (Review)
Review
Gonorrhea is a major, global public health problem for which there is no vaccine. The continuing emergence of antibiotic-resistant strains raises concerns that untreatable Neisseria gonorrhoeae may become widespread in the near future. Consequently, there is an urgent need for increased efforts towards the development of new anti-gonococcal therapeutics and vaccines, as well as suitable models for potential pre-clinical vaccine trials. Several current issues regarding gonorrhea are discussed herein, including the global burden of disease, the emergence of antibiotic-resistance, the status of vaccine development and, in particular, a focus on the model systems available to evaluate drug and vaccine candidates. Finally, alternative approaches to evaluate vaccine candidates are presented. Such approaches may provide valuable insights into the protective mechanisms, and correlates of protection, required to prevent gonococcal transmission, local infection and disease sequelae.
Topics: Animals; Bacterial Vaccines; Gonorrhea; Humans; Neisseria gonorrhoeae; Virulence
PubMed: 26805040
DOI: 10.3109/1040841X.2015.1105782 -
Human Vaccines & Immunotherapeutics 2015In recent years, nanomedicine has transformed many areas of traditional medicine, and enabled fresh insights into the prevention of previously difficult to treat...
In recent years, nanomedicine has transformed many areas of traditional medicine, and enabled fresh insights into the prevention of previously difficult to treat diseases. An example of the transformative power of nanomedicine is a recent nano-vaccine against listeriosis, a serious bacterial infection affecting not only pregnant women and their neonates, but also immune-compromised patients with neoplastic or chronic autoimmune diseases. There is a major unmet need for an effective and safe vaccine against listeriosis, with the challenge that an effective vaccine needs to generate protective T cell immunity, a hitherto difficult to achieve objective. Now utilizing a gold nanoparticle antigen delivery approach together with a novel polysaccharide nanoparticulate adjuvant, an effective T-cell vaccine has been developed that provides robust protection in animal models of listeriosis, raising the hope that one day this nanovaccine technology may protect immune-compromised humans against this serious opportunistic infection.
Topics: Adjuvants, Immunologic; Animals; Bacterial Vaccines; Disease Models, Animal; Drug Carriers; Drug Evaluation, Preclinical; Female; Gold; Listeriosis; Nanoparticles; Polysaccharides; T-Lymphocytes; Treatment Outcome
PubMed: 26252360
DOI: 10.1080/21645515.2015.1063756 -
Trends in Immunology Jul 2009Successful vaccination of the elderly against important infectious pathogens that cause high morbidity and mortality represents a growing public health priority.... (Review)
Review
Successful vaccination of the elderly against important infectious pathogens that cause high morbidity and mortality represents a growing public health priority. Building on the theme of aging and immunosenescence, we review mechanisms of human immunosenescence and the immune response to currently licensed vaccines. We discuss the difficulties in identifying the risk factors that, in addition to aging, cause immunosenescence and address the relative paucity of vaccine studies in the elderly. We conclude that vaccine responses are blunted in the elderly compared with that of healthy young adults. However, it is also clear that our understanding of the mechanisms underlying immunosenescence is limited and much remains to be learned to improve the effectiveness of next generation vaccines.
Topics: Aged; Aging; Antibody Formation; Bacterial Vaccines; Communicable Disease Control; Communicable Diseases; Humans; Immunity, Cellular; Vaccination; Viral Vaccines
PubMed: 19540808
DOI: 10.1016/j.it.2009.05.002 -
Clinical Microbiology and Infection :... Oct 2012Vaccines have a significant impact on public health, and vaccinology in the era of genomics is taking advantage of new technologies to tackle diseases for which vaccine... (Review)
Review
Vaccines have a significant impact on public health, and vaccinology in the era of genomics is taking advantage of new technologies to tackle diseases for which vaccine development has so far been unsuccessful. Almost all existing vaccines were developed based on traditional vaccinology methods, which relied on empirical screening of a few candidates at a time, based on known features of the pathogen. However, the ability to sequence a pathogen's genome provides access to its entire antigenic repertoire. As such, genomics has catalysed a shift in vaccine development towards sequence-based 'Reverse Vaccinology' approaches, which use high-throughput in silico screening of the entire genome of a pathogen to identify genes that encode proteins with the attributes of good vaccine targets. Furthermore, the increasing availability of genome sequences has led to the development and application of additional technologies to vaccine discovery, including comparative genomics, transcriptomics, proteomics, immunomics and structural genomics. Vaccine candidates identified from a pathogen's genome or proteome can then be expressed as recombinant proteins and tested in appropriate in vitro or in vivo models to assess immunogenicity and protection. The process of reverse vaccinology has been applied to several pathogens, including serogroup B Neisseria meningitidis, Streptococcus agalactiae, Streptococcus pyogenes, Streptococcus pneumoniae and pathogenic Escherichia coli, and has provided scores of new candidate antigens for preclinical and clinical investigation. As novel genome-based technologies continue to emerge, it is expected that new vaccines for unmet diseases will be within reach.
Topics: Bacterial Vaccines; Biotechnology; Computational Biology; Humans; Reverse Genetics; Technology, Pharmaceutical; Vaccination
PubMed: 22882709
DOI: 10.1111/j.1469-0691.2012.03939.x -
Future Microbiology Apr 2018
Topics: Animals; Anti-Bacterial Agents; Bacterial Vaccines; Disease Models, Animal; Drug Resistance, Multiple, Bacterial; Female; Gonorrhea; Humans; Male; Mice; Neisseria gonorrhoeae; Public Health; Vaccination
PubMed: 29517283
DOI: 10.2217/fmb-2017-0262