Assuntos
Vacinas contra COVID-19/provisão & distribuição , COVID-19/prevenção & controle , Adenoviridae/genética , Adulto , COVID-19/epidemiologia , COVID-19/imunologia , Vacinas contra COVID-19/economia , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Aprovação de Drogas , Fatores Econômicos , Humanos , Irã (Geográfico)/epidemiologia , Vírus do Sarampo/genética , Fosfoproteínas/genética , Fosfoproteínas/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de Produtos Inativados/genética , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/provisão & distribuição , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/provisão & distribuiçãoRESUMO
The World Health Organization (WHO) recommends the periodic evaluation of the purity of the cell lines used in the production of rabies vaccines, as well as the antigenic identity of the virus strains. Here, we analyzed seventeen marketed inactivated human rabies virus vaccines for viral and non-viral proteins by SDS-PAGE and Coomassie/silver staining. Mass spectrometric analysis of an abundant 60-70 kDa signal indicated that in most vaccines serum albumin of human origin (HSA) was the major component. Quantification of HSA in the vaccines revealed a mean concentration of 22 mg HSA/dose in all tested PVRV (purified vero cell rabies vaccine), HDCV (human diploid cell rabies vaccine) and PHK (primary hamster kidney) vaccines. In contrast, 1000-fold lower HSA levels and no HSA were detected in PCECV (purified chick embryo cell-culture vaccine) and PDEV (duck embryo rabies vaccine), respectively. Western blot analyses further confirmed a high bias in the HSA content, whereas the virus protein levels were rather similar in all tested vaccines. In addition, the vaccine viruses were sequenced within the N- and G-genes to identify the strain. In the majority of sequenced vaccines, the declared vaccine strain was confirmed. However, some discrepancies in the genetic identification were observed, supporting WHO's recommendation for the molecular characterization of vaccine seed strains. This research highlights the variation in purity found between different human rabies virus vaccines, and suggests that further research is needed to establish the impact non-active components have on the potency of such vaccines.
Assuntos
Vacina Antirrábica/imunologia , Animais , Western Blotting , Técnicas de Cultura de Células , Eletroforese em Gel de Poliacrilamida , Humanos , Espectrometria de Massas , Proteoma/análise , Vacina Antirrábica/química , Vacina Antirrábica/genética , Albumina Sérica/isolamento & purificação , Vacinas de Produtos Inativados/química , Vacinas de Produtos Inativados/genética , Vacinas de Produtos Inativados/imunologia , Proteínas Virais/genética , Proteínas Virais/isolamento & purificaçãoRESUMO
Over the past half-century, global use of highly effective vaccines against poliomyelitis brought this disease to the brink of elimination. Mounting evidence supports the argument that a high level of population immunity must be maintained after wild poliovirus circulation is stopped to preserve a polio-free status worldwide. Shifting factors in the risk-benefit-cost equation favor the creation of new poliovirus vaccines for use in the foreseeable future. Genetically stable attenuated virus strains could be developed for an improved oral poliovirus vaccine, but proving their safety and efficacy would be impractical owing to the enormous size of the clinical trials required. Novel versions of inactivated poliovirus vaccine that could be used globally should be developed. An improved inactivated poliovirus vaccine must be efficacious, inexpensive, safe to manufacture and easy to administer. Combination products containing inactivated poliovirus vaccine and other protective antigens should become part of routine childhood immunizations around the world.