Expert Review of Vaccines最新文献

Introduction: Hookworms infect about half a billion people worldwide and are responsible for the loss of more than two billion disability-adjusted life years. Mass drug administration (MDA) is the most popular preventive approach, but it does not prevent reinfection. An effective vaccine would be a major public health tool in hookworm-endemic areas.

Areas covered: We highlight recent human studies where vaccination with irradiated larvae and repeated rounds of infection-treatment have induced partial protection. These studies have emphasized the importance of targeting the infective larvae to generate immunity to prevent adult worms from maturing in the gut. We summarize the current status of human and animal model vaccine trials.

Expert opinion: Hookworm infection is endemic in resource-poor developing regions where polyparasitism is common, and vaccine cold chain logistics are complex. Humans do not develop sterile immunity to hookworms, and the elderly are frequently overlooked in MDA campaigns. For all these reasons, a vaccine is essential to create long-lasting protection. The lack of a robust animal model to mimic human hookworm infections is a barrier to the discovery and development of a vaccine, however, there have been major recent advances in human challenge studies which will accelerate the process.

Introduction: Persistent infections with the human papilloma viruses, HPV16 and HPV18, are associated with multiple cancers. Although prophylactic vaccines that induce HPV-neutralizing antibodies are effective against primary infections, they have no effect on HPV-mediated malignancies against which there is no approved immuno-therapy. Active research is ongoing on immunotherapy of these cancers.

Areas covered: In this review, we compared the preclinical efficacy of vaccine platforms used to treat HPV-induced tumors in the standard model of mice grafted with TC-1 cells, which express the HPV16 E6 and E7 oncoproteins. We searched for the key words, 'HPV,' 'vaccine,' 'therapy,' 'E7,' 'tumor,' 'T cells' and 'mice' for the period from 2005 to 2023 in PubMed and found 330 publications. Among them, we selected the most relevant to extract preclinical antitumor results to enable cross-sectional comparison of their efficacy.

Expert opinion section: We compared these studies for HPV antigen design, immunization regimen, immunogenicity, and antitumor effect, considering their drawbacks and advantages. Among all strategies used in murine models, certain adjuvanted proteins and viral vectors showed the strongest antitumor effects, with the use of lentiviral vectors being the only approach to result in complete tumor eradication in 100% of experimental individuals while providing the longest-lasting memory.

Introduction: The use of novel adjuvants in human vaccines continues to expand as their contribution to preventing disease in challenging populations and caused by complex pathogens is increasingly understood. AS01 is a family of liposome-based vaccine Adjuvant Systems containing two immunostimulants: 3-O-desacyl-4'-monophosphoryl lipid A and the saponin QS-21. AS01-containing vaccines have been approved and administered to millions of individuals worldwide.

Areas covered: Here, we report advances in our understanding of the mode of action of AS01 that contributed to the development of efficacious vaccines preventing disease due to malaria, herpes zoster, and respiratory syncytial virus. AS01 induces early innate immune activation that induces T cell-mediated and antibody-mediated responses with optimized functional characteristics and induction of immune memory. AS01-containing vaccines appear relatively impervious to baseline immune status translating into high efficacy across populations. Currently licensed AS01-containing vaccines have shown acceptable safety profiles in clinical trials and post-marketing settings.

Expert opinion: Initial expectations that adjuvantation with AS01 could support effective vaccine responses and contribute to disease control have been realized. Investigation of the utility of AS01 in vaccines to prevent other challenging diseases, such as tuberculosis, is ongoing, together with efforts to fully define its mechanisms of action in different vaccine settings.