Production Of Novel Vaccine Research Articles

Public Willingness to Participate in COVID-19 Vaccine Clinical Trials: A Study from Jordan.

PurposeThe development and production of novel vaccine to prevent COVID-19 is an international imperative to human lives. For that purpose, clinical trials have to be carried out as per international ethical standards. The current study was undertaken to examine the willingness to participate in COVID-19 vaccine clinical trials and to determine factors that might affect their decision to participate.Patients and MethodsA cross-sectional survey study was carried out among the public in Jordan. During the study period, a convenience sample of adults (aged 18 years or above) were asked to participate via an online self-administered survey that was designed to evaluate the willingness to participate in COVID-19 vaccine clinical trials and to determine factors affecting their decision to participate.ResultsResults showed that, among participants (n=1,287), 36.1% reported to be willing to participate in clinical trials of the vaccine. Additionally, a lower percentage (18.1%) were willing to allow their children to participate. Motivators that encourage participation were the desire to return to normal life (73.2%), followed by the desire to help in finding a treatment for COVID-19 infection (68.1%). Barriers towards the participation were not wanting to be challenged by the virus (54.7%), fear (40.7%), lack of time (40.4%), and mistrust in pharmaceutical companies (38.9%). Finally, results showed that higher educational level was associated with lower willingness to participate (P=0.001), whereas having a previous participation in clinical studies is associated with a significantly higher willingness to participate in COVID-19 vaccine clinical trials (P<0.001).ConclusionA good portion of Jordanians are positive regarding participation in clinical studies of COVID-19 vaccine. Educational level and previous participation in clinical studies were among the determinants of such willingness. In addition, fear and lack of time were among the barriers of participation.

Evaluation of recombinant outer membrane protein based vaccine against Salmonella Typhimurium in birds

Food-borne diseases caused by Salmonella enterica from poultry sources represent an important public health problem and no reliable control by vaccination has proved effective despite research. The aim of the present study was to evaluate the use of recombinant OmpC protein for immunization of birds to elucidate its protection against virulent Salmonella Typhimurium. The recombinant OmpC protein was prepared after cloning and expressing ompC gene and was characterized by SDS-PAGE and Western blot analyses. The protein preparations were tested as vaccine candidate in layer birds by comparing the immune response, protection and organ clearance against crude lysate and control. The biologically functional recombinant 43 kDa truncated OmpC protein proved to be a good immunogen which induced a significantly high humoral immune response than control. At the same time, it primed a stable cell-mediated immune response. A protective index (based on faecal shedding of organism) of rOmpC based preparations ranged between 50 and 75% as observed for 3 weeks after challenge. Therefore, the protein preparations conferred satisfactory protection against challenge infections with virulent strains of S. Typhimurium as evidenced by limited faecal shedding and minimal detection of Salmonella from edible tissues and eggs. These findings suggest the possibility to explore the use of S. enterica OMP protein for the production of novel vaccine.

Stability of a soybean seed‐derived vaccine antigen following long‐term storage, processing and transport in the absence of a cold chain

AbstractBACKGROUND: Soybean seeds are rich in natural protein and are favorable environments for targeted protein expression. Soybeans represent an ideal platform for the production of novel vaccines that, in theory, do not require a cold chain. This study investigated the stability of a soybean‐derived antigen following long‐term storage, formulation, and shipment overseas in the absence of refrigeration.RESULTS: Transgenic seeds can be stored for more than 4 years at ambient temperature with no detectable loss of FanC antigen stability. Conventional processing methods utilizing heat, mechanical extraction and solvent extraction resulted in practical formulations that could be lyophilized, stored as dried milk powder and rehydrated in water without loss of FanC antigen stability. Overseas shipment of transgenic seed powder and soymilk formulations in the absence of a cold chain had no adverse effects on formulations or the FanC antigen.CONCLUSION: The feasibility of long‐term storage, processing and shipment of transgenic soy products in the absence of a cold chain was demonstrated. Soybeans represent a practical platform for development of novel vaccines to potentially address the worldwide need for vaccines that are cost‐effective, easy to formulate and can be manufactured, stored and transported without refrigeration. Copyright © 2009 Society of Chemical Industry

Novel Vaccines: Bridging Research, Development and Production

Vaccines are among the greatest achievements of modern medicine, leading to the eradication of naturally occurring smallpox, the near elimination of polio and the control of diseases such as rotavirus and hepatitis A and B in industrialized countries. Conventional vaccines, however, protect against a limited number of infectious diseases and, in some cases, provide incomplete protection. Effective vaccines against common infections such as HIV, hepatitis C and malaria remain an unmet medical need. These gaps, together with the threat of resurgence of eradicated diseases, contribute to the growing need for the development of new vaccines and the improvement of existing ones. Approximately 250 scientists and vaccine experts from around the world gathered at Cambridge Healthtech Institute’s 3rd Annual Immunotherapeutics and Vaccine Summit (ImVacS 2008) to present the latest developments in this field and to discuss, in 64 presentations, the challenges and current approaches to development and production of novel vaccines.

Selectively receptor-blind measles viruses: Identification of residues necessary for SLAM- or CD46-induced fusion and their localization on a new hemagglutinin structural model.

Measles virus (MV) enters cells either through the signaling lymphocyte activation molecule SLAM (CD150) expressed only in immune cells or through the ubiquitously expressed regulator of complement activation, CD46. To identify residues on the attachment protein hemagglutinin (H) essential for fusion support through either receptor, we devised a strategy based on analysis of morbillivirus H-protein sequences, iterative cycles of mutant protein production followed by receptor-based functional assays, and a novel MV H three-dimensional model. This model uses the Newcastle disease virus hemagglutinin-neuraminidase protein structure as a template. We identified seven amino acids important for SLAM- and nine for CD46 (Vero cell receptor)-induced fusion. The MV H three-dimensional model suggests (i) that SLAM- and CD46-relevant residues are located in contiguous areas in propeller beta-sheets 5 and 4, respectively; (ii) that two clusters of SLAM-relevant residues exist and that they are accessible for receptor contact; and (iii) that several CD46-relevant amino acids may be shielded from direct receptor contacts. It appears likely that certain residues support receptor-specific H-protein conformational changes. To verify the importance of the H residues identified with the cell-cell fusion assays for virus entry into cells, we transferred the relevant mutations into genomic MV cDNAs. Indeed, we were able to recover recombinant viruses, and we showed that these replicate selectively in cells expressing SLAM or CD46. Selectively receptor-blind viruses will be used to study MV pathogenesis and may have applications for the production of novel vaccines and therapeutics.

DNA vaccine encoding pertussis toxin S1 subunit induces protection against Bordetella pertussis in mice

Pertussis toxin (PT) is the major virulence factor of Bordetella pertussis, and detoxified PT is a crucial antigen of acellular pertussis vaccine. Here, plasmid DNA expressing the pertussis toxin S1 subunit (pcDNA/S1) of B. pertussis was evaluated for immunogenicity and for the ability to induce protection against PT challenge or B. pertussis infection in mice. The gene gun delivery of pcDNA/S1, performed by inserting the S1 gene into a mammalian expression vector, successfully induced anti-PT IgG antibody production. Immunization of mice with pcDNA/S1 significantly inhibited leukocytosis-promoting activity caused by PT or B. pertussis. In addition, pcDNA/S1 induced significant protection against intracerebral challenge with a lethal dose of B. pertussis. The results of the present study demonstrated that a DNA vaccine encoding the PT-S1 subunit induced protection against B. pertussis infection in mice. Thus, this vaccine preparation is potentially applicable for the production of novel vaccines against B. pertussis infection.