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Microbiological Research Jun 2023Staphylococcus aureus (S. aureus) is a leading and crucial infectious threat to global public health due to the widespread emergence of antibiotic-resistant strains such... (Review)
Review
Staphylococcus aureus (S. aureus) is a leading and crucial infectious threat to global public health due to the widespread emergence of antibiotic-resistant strains such as Methicillin-Resistant S. aureus (MRSA). MRSA infects immunocompromised patients and healthy individuals and has rapidly spread from the healthcare setting to the outside community. The development of flawless vaccines become a medical need worldwide against multi-drug resistant S. aureus. Therefore, protection by an immune-based strategy may provide valuable measures to contain the spread of invasive S. aureus infections. Several vaccine candidates have been prepared which are either in the preclinical phase or in the early clinical phase, whereas several candidates have failed to show a protective efficacy in human subjects. Currently, research is focusing on identifying novel vaccine formulations able to elicit potent humoral and cellular immune responses. Several approaches have also been made to the development of monoclonal or polyclonal antibodies for passive immunization to protect against S. aureus infections. In recent years, a multi-epitope vaccine has emerged as a novel platform for subunit vaccine design by using computational approaches. Therefore, in this review, we have summarized and discussed the mechanistic overview of different strategies used to develop potential vaccine candidates and passive interventions which are in different stages of clinical trials to fight multi-drug resistant S. aureus infections.
Topics: Humans; Methicillin-Resistant Staphylococcus aureus; Staphylococcal Infections; Staphylococcal Vaccines; Staphylococcus aureus; Vaccine Development
PubMed: 36958134
DOI: 10.1016/j.micres.2023.127362 -
Journal of Medical Virology Oct 2022The global pandemic of COVID-19 began in December 2019 and is still continuing. The past 2 years have seen the emergence of several variants that were more vicious than... (Review)
Review
The global pandemic of COVID-19 began in December 2019 and is still continuing. The past 2 years have seen the emergence of several variants that were more vicious than each other. The emergence of Omicron (B.1.1.529) proved to be a huge epidemiological concern as the rate of infection of this particular strain was enormous. The strain was identified in South Africa on November 24, 2021 and was classified as a "Variant of Concern" on November 26, 2021. The Omicron variant possessed mutations in the key RBD region, the S region, thereby increasing the affinity of ACE2 for better transmission of the virus. Antibody resistance was found in this variant and it was able to reduce vaccine efficiency of vaccines. The need for a booster vaccine was brought forth due to the prevalence of the Omicron variant and, subsequently, this led to targeted research and development of variant-specific vaccines and booster dosage. This review discusses broadly the genomic characters and features of Omicron along with its specific mutations, evolution, antibody resistance, and evasion, utilization of CRISPR-Cas12a assay for Omicron detection, T-cell immunity elicited by vaccines against Omicron, and strategies to decrease Omicron infection along with COVID-19 and it also discusses on XE recombinant variant and on infectivity of BA.2 subvariant of Omicron.
Topics: COVID-19; Humans; Pandemics; SARS-CoV-2; Vaccine Development
PubMed: 35705439
DOI: 10.1002/jmv.27936 -
EBioMedicine Dec 2021COVID-19 has become a major cause of global mortality and driven massive health and economic disruptions. Mass global vaccination offers the most efficient pathway... (Review)
Review
COVID-19 has become a major cause of global mortality and driven massive health and economic disruptions. Mass global vaccination offers the most efficient pathway towards ending the pandemic. The development and deployment of first-generation COVID-19 vaccines, encompassing mRNA or viral vectors, has proceeded at a phenomenal pace. Going forward, nanoparticle-based vaccines which deliver SARS-CoV-2 antigens will play an increasing role in extending or improving vaccination outcomes against COVID-19. At present, over 26 nanoparticle vaccine candidates have advanced into clinical testing, with ∼60 more in pre-clinical development. Here, we discuss the emerging promise of nanotechnology in vaccine design and manufacturing to combat SARS-CoV-2, and highlight opportunities and challenges presented by these novel vaccine platforms.
Topics: Antibodies, Neutralizing; Antibodies, Viral; COVID-19; COVID-19 Vaccines; Humans; Immunogenicity, Vaccine; Liposomes; Nanoparticles; Pandemics; SARS-CoV-2; Vaccine Development
PubMed: 34801965
DOI: 10.1016/j.ebiom.2021.103699 -
BMC Health Services Research Mar 2023Various vaccines have been developed and distributed worldwide to control and cope with COVID-19 disease. To ensure vaccines benefit the global community, the ethical... (Review)
Review
BACKGROUND
Various vaccines have been developed and distributed worldwide to control and cope with COVID-19 disease. To ensure vaccines benefit the global community, the ethical principles of beneficence, justice, non-maleficence, and autonomy should be examined and adhered to in the process of development, distribution, and implementation. This study, therefore, aimed to examine ethical considerations of vaccine development and vaccination processes.
METHODS
A scoping review of the literature was conducted based on the Arkesy and O'Malley protocol to identify eligible studies published until November 2021. We searched Web of Science, PubMed, Scopus, and SciELO databases. The search was conducted using combinations of Medical Subject Heading (MeSH) search terms and keywords for Ethics, COVID-19, and vaccines in abstract, keywords, and title fields to retrieve potentially relevant publications. We included any study that reported one of the four principles of medical ethics: autonomy, justice, non-maleficence, and beneficence in the COVID-19 vaccine development and distribution and implementation of vaccinations. Letters, notes, protocols, and brief communications were excluded. In addition, we searched gray literature to include relevant studies (ProQuest database, conferences, and reports). Data were analyzed using framework analysis.
RESULTS
In total, 43 studies were included. Ethical considerations concluded two themes: (1) production and (2) distribution and vaccination. The production process consisted of 16 codes and 4 main Categories, distribution and vaccination process consisted of 12 codes and 4 main Categories. Moreover, the ethical considerations of special groups were divided into four main groups: health care workers (HCWs) (five codes), children and adolescents (five codes), the elderly (one code), and ethnic and racial minorities (three codes).
CONCLUSION
Due to the externalities of pandemics and the public and social benefits and harms of vaccination, it is not feasible to adhere to all four principles of medical ethics simultaneously and perfectly. This issue confronts individuals and policymakers with several moral dilemmas. It seems that decision-making based on the balance between social benefit and social harm is a better criterion in this regard, and the final decision should be made based on maximizing the public benefit and minimizing the public harm.
Topics: COVID-19 Vaccines; COVID-19; Vaccine Development; Ethics, Medical; Beneficence; Social Justice; Bioethics; Humans
PubMed: 36918888
DOI: 10.1186/s12913-023-09237-6 -
Expert Review of Vaccines Oct 2021A vaccine would greatly accelerate current global efforts toward malaria elimination. While a partially efficacious vaccine has been achieved for , a major bottleneck in... (Review)
Review
INTRODUCTION
A vaccine would greatly accelerate current global efforts toward malaria elimination. While a partially efficacious vaccine has been achieved for , a major bottleneck in developing highly efficacious vaccines is a lack of reliable correlates of protection, and the limited application of assays that quantify functional immune responses to evaluate and down-select vaccine candidates in pre-clinical studies and clinical trials.
AREAS COVERED
In this review, we describe the important role of antibodies in immunity against malaria and detail the nature and functional activities of antibodies against the malaria-causing parasite. We highlight the growing understanding of antibody effector functions against malaria and assays to measure these functional antibody responses. We discuss the application of these assays to quantify antibody functions in vaccine development and evaluation.
EXPERT OPINION
It is becoming increasingly clear that multiple antibody effector functions are involved in immunity to malaria. Therefore, we propose that evaluating vaccine candidates needs to move beyond individual assays or measuring IgG magnitude alone. Instead, vaccine evaluation should incorporate the full breadth of antibody response types and harness a wider range of assays measuring functional antibody responses. We propose a 3-tier approach to implementing assays to inform vaccine evaluation.
Topics: Antibodies, Protozoan; Antigens, Protozoan; Humans; Malaria; Malaria Vaccines; Malaria, Falciparum; Plasmodium falciparum; Vaccine Development
PubMed: 34530671
DOI: 10.1080/14760584.2021.1981864 -
The American Journal of Medicine Mar 2022
Topics: Humans; Vaccine Efficacy
PubMed: 34614396
DOI: 10.1016/j.amjmed.2021.09.002 -
Reviews in Medical Virology Mar 2023Dengue illness can range from mild illness to life-threatening haemorrhage. It is an Aedes-borne infectious disease caused by the dengue virus, which has four serotypes.... (Review)
Review
Dengue illness can range from mild illness to life-threatening haemorrhage. It is an Aedes-borne infectious disease caused by the dengue virus, which has four serotypes. Each serotype acts as an independent infectious agent. The antibodies against one serotype confer homotypic immunity but temporary protection against heterotypic infection. Dengue has become a growing health concern for up to one third of the world's population. Currently, there is no potent anti-dengue medicine, and treatment for severe dengue relies on intravenous fluid management and pain medications. The burden of dengue dramatically increases despite advances in vector control measures. These factors underscore the need for a vaccine. Various dengue vaccine strategies have been demonstrated, that is, live attenuated vaccine, inactivated vaccine, DNA vaccine, subunit vaccine, and viral-vector vaccines, some of which are at the stage of clinical testing. Unfortunately, the forefront candidate vaccine is less than satisfactory, and its performance depends on serostatus and age factors. The lessons from clinical studies depicted ambiguity concerning the efficacy of dengue vaccine. Our study highlighted that viral structural heterogeneity, epitope accessibility, autoimmune complications, genetic variants, genetic diversities, antigen competition, virulence variation, host-pathogen specific interaction, antibody-dependent enhancement, cross-reactive immunity among Flaviviruses, and host-susceptibility determinants not only influence infection outcomes but also hampered successful vaccine development. This review integrates dengue determinants allocated necessities and challenges, which would provide insight for universal dengue vaccine development.
Topics: Animals; Humans; Antibodies, Viral; Dengue Vaccines; Dengue Virus; Mosquito Vectors; Viral Vaccines; Vaccine Development
PubMed: 36683235
DOI: 10.1002/rmv.2425 -
Current Drug Targets 2023Leishmaniasis is one of the Neglected Tropical Diseases (NTDs), a zoonotic disease of vector-borne nature that is caused by a protozoan parasite . This parasite is...
Leishmaniasis is one of the Neglected Tropical Diseases (NTDs), a zoonotic disease of vector-borne nature that is caused by a protozoan parasite . This parasite is transmitted by the vector sandfly into the human a bite. Visceral leishmaniasis (VL), also called kala-azar, is the most fatal among the types of leishmaniasis, with high mortality mostly spread in the East Africa and South Asia regions. WHO report stated that approximately 3.3 million disabilities occur every year due to the disease along with approximately 50,000 annual deaths. The real matter of concern is that there is no particular effective medicine/vaccine available against leishmaniasis to date except a few approved drugs and chemotherapy for the infected patient. The current selection of small compounds was constrained, and their growing drug resistance had been a major worry. Additionally, the serious side effects on humans of the available therapy or drugs have made it essential to discover efficient and low-cost methods to speed up the development of new drugs against leishmaniasis. Ideally, the vaccine could be a low risk and effective alternative for both CL and VL and elicit long-lasting immunity against the disease. There are a number of vaccine candidates at various stages of clinical development and preclinical stage. However, none has successfully passed all clinical trials. But, the successful development and approval of commercially available vaccines for dogs against canine leishmaniasis (CanL) provides evidence that it can be possible for humans in distant future. In the present article, the approaches used for the development of vaccines for leishmaniasis are discussed and the progress being made is briefly reviewed.
Topics: Animals; Dogs; Humans; Leishmania donovani; Leishmaniasis; Leishmaniasis, Visceral; Neglected Diseases; Vaccines; Vaccine Development
PubMed: 37823567
DOI: 10.2174/0113894501254585230927100440 -
Cellular Immunology 2024Infectious diseases like leishmaniasis, malaria, HIV, tuberculosis, leprosy and filariasis are responsible for an immense burden on public health systems. Among these,... (Review)
Review
Infectious diseases like leishmaniasis, malaria, HIV, tuberculosis, leprosy and filariasis are responsible for an immense burden on public health systems. Among these, leishmaniasis is under the category I diseases as it is selected by WHO (World Health Organization) on the ground of diversity and complexity. High cost, resistance and toxic effects of Leishmania traditional drugs entail identification and development of therapeutic alternative. Since the natural infection elicits robust immunity, consistence efforts are going on to develop a successful vaccine. Clinical trials have been conducted on vaccines like Leish-F1, F2, and F3 formulated using specific Leishmania antigen epitopes. Current strategies utilize individual or combined antigens from the parasite or its insect vector's salivary gland extract, with or without adjuvant formulation for enhanced efficacy. Promising animal data supports multiple vaccine candidates (Lmcen-/-, LmexCen), with some already in or heading for clinical trials. The crucial challenge in Leishmania vaccine development is to translate the research knowledge into affordable and accessible control tools that refines the outcome for those who are susceptible to infection. This review focuses on recent findings in Leishmania vaccines and highlights difficulties facing vaccine development and implementation.
Topics: Humans; Leishmaniasis Vaccines; Animals; Leishmania; Leishmaniasis; Vaccine Development; Antigens, Protozoan; Clinical Trials as Topic
PubMed: 38669897
DOI: 10.1016/j.cellimm.2024.104826 -
Toxins Sep 2021Possible implications and applications of the yeast killer phenomenon in the fight against infectious diseases are reviewed, with particular reference to some... (Review)
Review
Possible implications and applications of the yeast killer phenomenon in the fight against infectious diseases are reviewed, with particular reference to some wide-spectrum killer toxins (KTs) produced by and other related species. A perspective on the applications of these KTs in the medical field is provided considering (1) a direct use of killer strains, in particular in the symbiotic control of arthropod-borne diseases; (2) a direct use of KTs as experimental therapeutic agents; (3) the production, through the idiotypic network, of immunological derivatives of KTs and their use as potential anti-infective therapeutics. Studies on immunological derivatives of KTs in the context of vaccine development are also described.
Topics: Anti-Infective Agents; Communicable Diseases; Cytotoxins; Humans; Killer Factors, Yeast; Saccharomycetales; Vaccine Development
PubMed: 34564659
DOI: 10.3390/toxins13090655